SETRA_Design and execution of earthworks_1 _2007+++++++++++++++++

march 2007

Technical guide

Design and execution of earthworks Section 1: Design and execution of work

The Technical Department for Transport, Roads and Bridges Engineering and Road Safety (Service d’études techniques des routes et autoroutes - Sétra) is a technical department within the Ministry of Transport and Infrastructure. Its field of activities consists of road, transportation and engineering structures. Sétra supports the public owner Sétra supplies State agencies and local communities (counties, large cities and urban communities) with information, methodologies and tools suited to the specificities of the networks in order to: • • • • • •

improve project quality; help with asset management; define, apply and evaluate public policies; guarantee the coherence of the road network and state-of-the art techniques; promote the public interest, in particular within the framework of European standardization; contribute expertise to complex projects.

Sétra, promoting state-of-the-art know-how On an extremely large scale, beyond road and engineering structures, in the field of transport, intermodality and sustainable development, Sétra: • • • • •

takes into account the needs of project owners and prime contractors, managers and operators; fosters exchanges of experience; evaluates technical progress and scientific results; develops knowledge and good practices through technical guides and software; contributes to the training and information of the technical community.

Sétra, working in partnership •

Sétra associates all the players in the French road construction community with its activities: operational services; research organizations; the Scientific and Technical Network (Réseau Scientifique et Technique de l’Equipement – RST), in particular the Public Works Regional Engineering Offices (Centres d’études techniques de l’Equipement – CETE), companies and professional organizations; motorway concessionary operators; other organizations such as the French Rail Network Company (Réseau Ferré de France – RFF) and the French Waterways Network (Voies Navigables de France - VNF); and government departments such as the Department for Ecology and Sustainable Development, and so on.

•

Sétra regularly exchanges its experience and projects with foreign counterparts, through bilateral cooperation programs, presentations in conferences and congresses, by hosting foreign delegations, and through assignments and consultancy work in other countries. It takes part in the European standardization commissions and many international authorities and working groups. Sétra is an organization for technical approval, as a member of EOTA (European Organization for Technical Approvals).

Technical guide

Design and execution of earthworks Section 1: Design and execution of work

This document is the translation of "Conception et réalisation des terrassements – Fascicule 1 : études et exécution des travaux" published in March 2007 as reference 0702-1.

Design and execution of earthworks – Section 1: studies and execution of work – Technical guide

This technical guide was drawn up within the framework of activities by the “methodology” sectorial committee of the French Road Engineering Committee (Comité français pour les techniques routières) (CFTR), by a working group made up of representatives of the Scientific & Technical Network of the French Ministry for Transport, Infrastructure, Tourism and the Sea, and the technical departments of contractors and producers in the roads sector. Its contents were subject to a validation inquiry with the various members of the CFTR.

Editing committee: •

Claude Aimé (DTPTerrassement (Earthworks))

•

Jean-Claude Auriol (LCPC Nantes)

•

Louis Robert Borrel (RAZEL)

•

Sylvain Brouard (SCETAUROUTE)

• Gérard Chanrion (DDE 34 (District-Level Office for Infrastructure Direction Départementale de l’Equipement)) • Abel Delfaut (DREIF - LROP (Region-level Offices for Infrastructure, Directions régionales de l'Equipiment)) •

Yves Deniel (DDE 28)

•

Claude Deschamps (Sétra)

•

Catherine Drouaux (Sétra)

• Alain Fèvre (Cete Normandie-Center - LR, Rouen Bordeaux (Technical Engineering Centers for Infrastructure, Centres d'Etudes Techniques de l'Equipement)) •

Pascal Fournier (District Assembly 78)

•

Daniel Gandille (GUINTOLI)

•

Thierry Gosselin (SCETAUROUTE)

•

Yves Guerpillon (SCETAUROUTE)

•

Hervé Havard (LCPC Nantes)

•

Jean-Pierre Joubert (Sétra)

•

Michel Kergoët (DREIF - LREP)

•

Gilles Lacassy (Cete du Sud-Ouest - LR,)

•

Jean-Pierre Lejeune (SCETAUROUTE)

•

Vincent Martin (SCETAUROUTE)

•

Claude Maury (GTM - Construction)

•

Thierry Mollier (SCETAUROUTE)

•

Marcel Mudet (SNCF)

•

Pierre Olivier (VALERIAN)

•

Michel Peyron (Cete Méditerranée)

•

Christophe Poilpré (GTS)

•

Michel Recourt (Cete Nord-Picardie)

•

Pierre Rossi (RAZEL)

•

Henri-Pierre Robert (DDE 76)

Collection « Les outils” – Sétra

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Introduction The objective of this “Design and execution of earthworks” guide is to assist and advise the construction manager from the time of preparation of the final design up until the execution of the earthworks. It consists of 3 separate sections: • this Section 1: design and execution of the works; • Section 2: organization of checks; • Section 3: test procedures. General earthworks in road operations constitute an important phase of studies, design and construction work requiring a high level of skills across a wide range of areas, particularly in the geotechnical field, but also in relation to the environment and sustainable development. Geotechnical surveys, which are essential for earthworks, must be accurate and complete to avoid technical and financial uncertainties which could entail additional or unforeseen extra costs of over 20%. A large number of general and special structures created and published by the CFTR and Sétra set out an accurate view of investigation, classification and treatment of soils and certain specific structures – i.e., blasting earthworks, embankments or fills on compressible soils, the approach in relation to quality and the utilization of soils for green roadside ancillaries. The aim of this guide to the design and construction of earthworks is to understand the issues involved in earthworks in relation to protection of the environment as of the initial alignment studies, complete all existing technical documentation, and use practical reports to set out the main features of existing information. It is mainly intended for experienced project design managers or construction managers to: • check that all the points to be examined at each phase of the preliminary studies, the overview / background summary [APS] and the project studies have been implemented, and that the feasibility of the part of the structure examined has not been called into question (chapter A); • understand a technology by means of a summary file listing the problems, the influential factors, the points to be examined and recommendations at the works stage (chapter B); • deepen and develop more detailed expertise with regard to the difficulties involved in designing and building special structures (chapters C, D and F); • optimize the writing of tender documents [DCE] for earthworks and construction work preparations (all chapters); • control the quality of a project or constructional measures at the construction work stage on motorway operations or much smaller operations such as a district road in an area with an extremely sensitive environment, or in a difficult geotechnical context (chapters A, B and C).


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Contents Sétra supports the public owner ...................................................................................2 Sétra, promoting state-of-the-art know-how ................................................................2 Sétra, working in partnership.......................................................................................2

Introduction .............................................................................................................. 6 Contents..................................................................................................................... 7 Chapter A – Studies of earthworks and the environment.................................. 12 A.1 - General ........................................................................................................ 12 A.2 – General principles of alignment studies ..................................................... 12 A.2.1 – Preliminary studies ........................................................................................12 A.2.2 – Overview / background summary [APS] .......................................................13 A.2.3 – Project studies................................................................................................13

A.3 – Consideration of the environment in earthworks studies ........................... 14 (see table) ........................................................................................................... 14 A.3.1 – A solution in terms of earthworks ..................................................................14 A.3.2 – A choice of solutions ......................................................................................14 A.3.3 – Areas for reflection and studies .....................................................................14

A.4 – Earthworks at all stages of studies.............................................................. 29 A.4.1.1 –Minor cuts (≤ 3 m) .......................................................................................29 A.4.1.2 –Minor embankments & fills (≤ 3 m) .............................................................38 A.4.3 – Large embankments/fills (> 3 m) ...................................................................47 A.4.4 – Large tall embankments/fills..........................................................................47

A.5 - Measurements.............................................................................................. 48 A.5.1 - Definition ........................................................................................................48 A.5.2 – Basic factors used for calculation..................................................................48 A.5.3 – Basic formula for measurement calculations.................................................48 A.5.4 – Approximate methods.....................................................................................49 A.5.5 – Computer methods .........................................................................................51 A.5.6 – Calculation method used by software ............................................................51 A.5.7 – Example of calculation of measurements.......................................................54 A.5.8 – Assistance software developed by SCETAUROUTE......................................57

B – Earthworks technology ................................................................................... 63 B.1 – Clearance of land requirements .................................................................. 63 B.1.1 – Area concerned ..............................................................................................63 B.1.2 – Technical referential......................................................................................63 B.1.3 – Issues involved ...............................................................................................63 B.1.4 – Influential parameters....................................................................................63 B.1.5 – Execution phasing..........................................................................................64 B.1.6 – Monitoring to be carried out..........................................................................64

B.2 – Site roads..................................................................................................... 65 B.2.1 – Area concerned ..............................................................................................65 B.2.2 – Technical referential......................................................................................65 B.2.3 – Issues involved ...............................................................................................65 B.2.4 - Influential parameters ....................................................................................65 B.2.5 – Execution phasing..........................................................................................65 B.2.6 – Monitoring to be carried out..........................................................................65 Collection « Les outils” – Sétra

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B.3 – Weather conditions and earthworks............................................................ 67 B.3.1 – Area concerned ..............................................................................................67 B.3.2 – Technical reference documents......................................................................67 B.3.3 - Issues involved................................................................................................67 B.3.4 – Influential parameters....................................................................................67 B.3.5 – Execution phasing..........................................................................................68 B.3.6 - Monitoring to be carried out ..........................................................................68

B.4 - Topsoil......................................................................................................... 69 B.4.1 - Area concerned...............................................................................................69 B.4.2 – Technical referential......................................................................................69 B.4.3 - Issues involved................................................................................................69 B.4.4 - Influential parameters ....................................................................................69 B.4.5 - Execution phasing...........................................................................................70 B.4.6 - Monitoring to be carried out ..........................................................................71

B.5 - Cuts.............................................................................................................. 72 B.5.1 - Area concerned...............................................................................................72 B.5.2 - Technical reference documents ......................................................................72 B.5.3 - Issues involved................................................................................................72 B.5.4 - Influential parameters ....................................................................................72 B.5.5 - Execution phasing for cuts..............................................................................73 B.5.6 - Monitoring to be carried out ..........................................................................74

B.6 - Embankments & Fills .................................................................................. 75 B.6.1 - Area concerned...............................................................................................75 B.6.2 - Technical referential.......................................................................................75 B.6.3 - Issues involved................................................................................................75 B.6.4 - Influential parameters ....................................................................................75 B.6.5 - Execution phasing for the embankment ..........................................................76

B.7 – External fillers or borrowings ..................................................................... 78 B.7.1 - Area concerned...............................................................................................78 B.7.2 - Technical referential.......................................................................................78 B.7.3 - Issues involved................................................................................................78 B.7.4 - Influential parameters ....................................................................................78 B.7.5 - Execution phasing for borrowing ...................................................................79 B.7.6 - Monitoring to be carried out ..........................................................................79

B.8 – Final deposits and earth mound barriers ..................................................... 80 B.8.1 - Area concerned...............................................................................................80 B.8.2 - Technical referential.......................................................................................80 B.8.3 - Issues involved................................................................................................80 B.8.4 - Influential parameters ....................................................................................80 B.8.5 - Execution phasing of a deposit and an earth mound barrier .........................81

B.9 – Embankments & fills on compressible soil ................................................ 82 B.9.1 - Area concerned...............................................................................................82 B.9.2 - Technical referential.......................................................................................82 B.9.3 - Issues involved................................................................................................82 B.9.4 - Influential parameters ....................................................................................82 B.9.5 - Solutions advocated ........................................................................................82 B.9.6 - Execution phasing...........................................................................................84 B.9.7 - Monitoring to be carried out ..........................................................................85

B.10 – Blasting earthworks .................................................................................. 86 B.10.1 - Area concerned.............................................................................................86 B.10.2 - Technical referential.....................................................................................86 B.10.3 - Issues involved..............................................................................................86 B.10.4 - Influential parameters ..................................................................................86 B.10.5 - Execution phasing.........................................................................................87 Collection « Les outils” – Sétra

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B.10.6 - Monitoring to be carried out ........................................................................88

B.11 – Waste and by-products.............................................................................. 89 B.11.1 - Area concerned.............................................................................................89 B.11.2 - Technical referential.....................................................................................89 B.11.3 - Issues involved..............................................................................................90 B.11.4 - Influential parameters ..................................................................................90 B.11.5 - Execution phasing.........................................................................................91 B.11.6 - Monitoring to be carried out ........................................................................93

B.12 – Sewerage and drainage ............................................................................. 94 B.12.1 - Area concerned.............................................................................................94 B.12.2 - Technical referential.....................................................................................94 B.12.3 - Issues involved..............................................................................................94 B.12.4 - Influential parameters ..................................................................................95 B.12.5 - Execution phasing.........................................................................................96 B.12.6 - Monitoring to be carried out ........................................................................96

B.13 - Capping layer............................................................................................. 97 B.13.1 - Area concerned.............................................................................................97 B.13.2 - Technical referential.....................................................................................97 B.13.3 - Issues involved..............................................................................................97 B.13.4 - Influential parameters ..................................................................................97 B.13.5 - Execution phasing for a capping layer .........................................................98

C – Special structures and particular points ....................................................... 99 C.1 – Embankments & fills next to structures...................................................... 99 C.1.1 - Area concerned...............................................................................................99 C.1.2 – Reference documents .....................................................................................99 C.1.3 - Issues involved................................................................................................99 C.1.4 - Solutions normally recommended ..................................................................99 C.1.5 - Implementation.............................................................................................100 C.1.6 – Special systems ............................................................................................100 C.2.1 - Area concerned.............................................................................................101 C.2.2 – Reference documents ...................................................................................101 C.2.3 - Issues involved..............................................................................................101 C.2.4 – Recommended solution ................................................................................101 C.2.5 – Development of a cut/embankment boundary in the project's cross section101

C.3 – Compaction of embankment edges........................................................... 103 C.3.1 – Area of application ......................................................................................103 C.3.2 - Reference documents....................................................................................103 C.3.3 - Issues involved..............................................................................................103 C.3.4 – Recommended solution – advantages/disadvantages ..................................103 C.3.5 - Mode of execution ........................................................................................104 C.3.6 – Checks and implementation .........................................................................104 C.3.7 - Remarks ........................................................................................................104

C.4 – Purging and substitution ........................................................................... 105 C.4.1 - Area concerned.............................................................................................105 C.4.2 - Reference documents....................................................................................105 C.4.3 - Definition of purging ....................................................................................105 C.4.4 - Definition of a substitution ...........................................................................105 C.4.5 - Issues involved..............................................................................................105 C.4.6 - Recommended solution.................................................................................107 C.4.7 - Remarks ........................................................................................................108

C.5 – Extra-large embankments/fills.................................................................. 109 C.5.1 - Area concerned.............................................................................................109 C.5.2 - Reference documents....................................................................................109 Collection « Les outils” – Sétra

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C.5.3 - Issues involved..............................................................................................109 C.5.4 – Studies to be arranged .................................................................................109 C.5.5 – Contents of a design study ...........................................................................110 C.5.6 – Guidelines for construction stipulations and choice of embankment materials111 C.5.7 – Monitoring and instrumentation program...................................................115

C.6 – Heterogeneous embankments/fills............................................................ 117 C.6.1 - Area concerned.............................................................................................117 C.6.2 - Reference documents....................................................................................117 C.6.3 - Issues involved..............................................................................................117 C.6.4 – Recommended solutions...............................................................................119 C.6.5 - Observations.................................................................................................120

C.7 – Embankments & fills with extra-dry materials......................................... 122 C.7.1 - Area concerned.............................................................................................122 C.7.2 - Reference documents....................................................................................122 C.7.3 - Issues involved..............................................................................................122 C.7.4 – The materials concerned..............................................................................122 C.7.5 - Solution envisaged........................................................................................122 C.8.1 - Area concerned.............................................................................................125 C.8.2 - Reference documents....................................................................................125 C.8.3 - Issues involved..............................................................................................125 C.8.4 – Recommended solutions...............................................................................125 C.8.5 – Construction stipulations.............................................................................126 C.8.6 - Observations.................................................................................................126

C.9 – Cuts/embankments/fills on a waste dump or a polluted site..................... 127 C.9.1 - Area concerned.............................................................................................127 C.9.2 - Reference documents....................................................................................127 C.9.3 - Issues involved..............................................................................................127 C.9.4 – Preliminary tests and investigation work ....................................................127 C.9.5 – Recommended solutions - implementation ..................................................128

C.10 – Cuts in aquiferous zones ......................................................................... 131 C.10.1 – Structure concerned...................................................................................131 C.10.2 - Reference documents ..................................................................................131 C.10.3 - Issues involved............................................................................................131 C.10.4 – Studies to be carried out ............................................................................132 C.10.5 – Recommended solutions.............................................................................134 C.10.6 - Observations...............................................................................................137

C.11 – Embankments & fills in aquiferous zones .............................................. 137 C.11.1 – Structures concerned .................................................................................137 C.11.2 - Reference documents ..................................................................................137 C.11.3 - Issues involved............................................................................................138 C.11.4 - Studies ........................................................................................................138 C.11.5 – Recommended solutions.............................................................................138

C.12 – Underground cavities.............................................................................. 140 C.12.1 - Area concerned...........................................................................................140 C.12.2 - Reference documents ..................................................................................140 C.12.3 - Issues involved............................................................................................140 C.12.4 – Studies to be carried out ............................................................................140 C.12.5 - Recommended solutions .............................................................................141

D – Constructional measures (case studies)....................................................... 143 Case study No. 1................................................................................................. 144 Case study No. 2................................................................................................. 145 Case study No. 3................................................................................................. 146 Collection « Les outils” – Sétra

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Case study No. 4................................................................................................. 148 Case study No. 5................................................................................................. 150 E – Preparation of work ...................................................................................... 153 E.1 – Design and analysis of variants................................................................. 153 E.1.1 – General stipulations and stipulations in regulations ...................................153 E.1.2 - Application to earthwork sites ......................................................................153 E.1.3 – Plausible variants ........................................................................................154 E.1.4 – Technical analysis of the variants................................................................154

E.2 – Legal, technical and economic risks in relation to earthworks ................. 156 E.2.1 – Risk assessment............................................................................................156 E.2.2 - Legal risks in relation to earthworks............................................................156 E.2.3 – Technical risks in relation to earthworks ....................................................157 E.2.4 – Economic risks in relation to earthworks ....................................................158

E.3 – Phases prior to construction ...................................................................... 160 E.3.1 – Concerning the Tender Documents [DCE] during the period of preparation160 E.3.2 – Inventory of the tools required for proper site construction........................163 E.3.3 – Earth movement and choice of materials.....................................................164

E.4 – Work phase ............................................................................................... 168 E.4.1 – Procedures to be observed during the work phase ......................................168 E.4.2 – Ordering of tasks..........................................................................................176

F - Pathologies....................................................................................................... 183 F.1 – Pathology of earthworks structures ........................................................... 183 F.1.1 - Preamble.......................................................................................................183 F.1.2 – Pathology of cuts..........................................................................................183 F.1.3 – Pathology of embankments and fills ............................................................184

Annexes ................................................................................................................. 186 Acronyms used ................................................................................................... 186 Bibliography ....................................................................................................... 189 Guides, notes and recommendations........................................................................189

Regulations ......................................................................................................... 190 Other documents................................................................................................. 191


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Chapter A – Studies of earthworks and the environment A.1 - General Before work is carried out, all road authorities and project owners must observe specific study and design procedures, regardless of whether these concern conceded or non-conceded motorway projects, state highways or district roads. Nomenclature and sequence of procedures fluctuate in accordance with the road authorities. Three major stages are generally implemented, as follows: 1) Preliminary Studies (EP), 2) Overview / background summary (APS), 3) Project studies (P).

A.2 – General principles of alignment studies A.2.1 – Preliminary studies The aims of these studies are as follows: • to define a study strip of at least 1,000 meters; • to define the general development scheme and the functions to be performed by the planned infrastructure; • to ensure the project’s technical, environmental and financial feasibility. In order to verify technical and environmental feasibility, and to implement dialogue geared towards a more global and less sectorial approach to planning, it is essential to gather at least a minimum amount of data for the entire study area in the following fields: • town planning; • assets; • nature areas; • forestry; • agricultural parcels; • geology and hydrogeology; • landscapes with a definition of sequences and positive points to be preserved, assisted or strengthened. It is not difficult to list data for the first four fields since this information is available free of charge from the DDE and DRAC, DIREN, DDAF. However, agricultural parcels, geology and hydrogeology, or even a flora and fauna study in certain cases, require specific detailed studies assisted by private engineering firms or public entities (such as CETE).


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These studies must be started as of the preliminary studies stage in order to take account of the following: • large single tracts of farmland, which may constitute a considerable constraint; • the feasibility of land reallocation and defining passage corridors with the agricultural profession; • major plausible geological difficulties, which are studied by means of bibliographic research and observations of field observations; • the hydrogeological impact that is liable to call a project into question, particularly in areas where there is lowdensity occupation of land. All this data, which is essential for a solid consultation policy that should be developed as of this stage of investigation of passage areas, will ultimately produce a quality project in relation to which all citizens will have made a contribution through decision-making processes.

A.2.2 – Overview / background summary [APS] Overview / background summary [APS] studies will consist of setting several alignments over a strip of 300 meters maximum (this length will be submitted to the public inquiry) inside the passage areas (maximum 1,000 meters) approved by preliminary studies and agreements between elected parties, citizens and associations. In order define the layout and depth of the bores required for investigation and reutilization of soil, a search should be made firstly for factors that are liable to call the project into question (compressible zones, karstic zones, general instability, etc.) and, secondly, for large-mass earthwork balance (study of longitudinal section). On the basis of the geotechnical report and the geological model attached with the report, modifications to the longitudinal section will be made in accordance with needs in order to preserve the balance of the terrain and to avoid generating waste by surplus materials. At this stage, coordination meetings will be held to present geotechnical constraints and their effects on the road’s alignment (land requirement), longitudinal section and the environment (protection from noise, management of surpluses or borrowed material in due observation of laws in force, perception of the project and landscapes).

A.2.3 – Project studies The objective of project studies is to determine all the geometric and technical characteristics of all structures. Additional boring will often be required in order to: • take account of the opinions expressed at the public inquiry and consultation meetings in relation to sewerage and drainage; • proceed with additional investigations in relation to the final alignment which may have been changed on plans and longitudinal section on request by residents between the overview / background summary [APS] stage and the project studies stage; • complete geotechnical studies, particularly concerning reusable materials and stability studies. Investigation of all solutions producing earth balance must be an absolute priority. One must resist the urge to place the entire project underground. Instead, one must develop a line of argument in relation to safety, user behavior patterns, user entitlement to landscape and tourism, and attempt to reduce transport distances and keep project economy in mind. The most plausible meteorological conditions with allotment of the earthworks contract must be considered at the level of the geotechnical report, but also in the reutilization percentages study and in the earthmoving program.


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A.3 – Consideration of the environment in earthworks studies (see table) As of the preliminary studies, the issue of the environment must be integrated in all areas covered by the circular of 1994 – as identified by the DIREN in the context of the circular of 18 September 1999 – at the time of presentation of projects at each progressive stage of the studies, and by the evaluation committee when it was implemented in connection with the environmental monitoring and evaluation guide issued by the Ministry for the Environment in 2001. In order to identify as many plausible solutions as possible for environmental problems in terms of earthworks, proposals have been summarized in tables for each study with regard to the following: • habitat; • agriculture; • forestry; • underground resources; • leisure activities; • fauna; • flora; • water; • soils; • assets; • landscape; • restoration of roads.

A.3.1 – A solution in terms of earthworks • carrying out a project based on the natural ground (TN); • carrying out a project by means of cuts (D); • carrying out a project by means of embankments and fills (R).

A.3.2 – A choice of solutions • the recommended solutions are shown in the column for longitudinal section in blue; • acceptable solutions are shown in yellow; • solutions to be avoided are shown in orange. N.B.: Certain types of longitudinal section have no incidence on these areas, and in this case no color is shown in the table.

A.3.3 – Areas for reflection and studies Analyses and studies to be performed mainly when solutions to be avoided are chosen due to local constraints or to the impossibility of carrying out a project elsewhere.


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Collection and external constraints Level of study

Environment concerned

Longitudinal section TN

Agriculture

Forestry

R

View, noise, air

• soil quality; • rocky soil (mining): • land requirement: • embankment/fill restorations.

Local access

Preferably accept road restorations where there are no clearance constraints, excluding junctions at grade.

• pedestrian and cyclist continuity, including on junction at grade; • land requirement on secondary roads. Do not forget pipelines, gas pipelines, etc.

EDF network

Investigation of alignment with no modification of the overhead system, particularly very high voltage.

Land requirement

On the basis of collation of agricultural data, avoid large single tracts of farmland as much as possible, and examine the feasibility of land reallocation. Inventory of areas for potential borrow pits or deposits.

Agreement with DIREN.

Redevelopment

Drained parcel

Inventory during collation of agricultural data.

Restoration of mechanism and of the outlet.

Market gardening

Inventory during collation of agricultural data of the nature of market gardening and method used for water supplies.

Arrange for studies on air and maintenance of water resources.

Forest assets

• exploit information from DIREN, DDAF and CRPF for private forests; • arrangement for compensatory reforestation surfaces by reducing parceling.

• blocks management plan to be reviewed; • cut and cover may be a solution in certain cases (in the case of major cuts).

Underground Protection and water maintenance of resources the resource


Additional analyses and consequences

Tendency towards solution involving a 3-m cut. If this is impossible, noise protection and protection of the landscape must be envisaged (mineral structure or earth mound barrier).

Habitat

PRELIMIN ARY STUDY

D

Analyses and studies to be performed

• exhaustive inventory of • restore the routes of tapping, wells, etc. which can resurgence and sources provide a direct link between (maintain initial balances); the surface and the resource; • determine the type of • determine the degree of systemic studies to be vulnerability of the study conducted and the extra zones and internal water costs arising from special routes. construction devices and measures (waterproofing, drainage, etc.). – 15 –

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Level of study



PRELIMIN ARY STUDY

Leisure

View, noise, air

Fauna

Cutting Isolation

Flora

Protected specificity

Roadbed water

Roadbed water outlet

Surface water

Area liable to flooding

Materials

Soil

Underground (identified)

Bearing capacity


D



R Tendency towards solution involving a 3-m embankment/fill. If this is impossible, noise protection and protection of the landscape must be envisaged (mineral structure or earth mound barrier).

• soil quality; • rocky soil (mining): • land requirement: • embankment/fill restorations.

• the upper passage for

Cut project favorable for PS, presents bared surfaces of roots from peak downslopes and hydromorphy in soils linked to border effect.

large fauna is preferable to the lower passage, although some function extremely well (precise identification of passage areas); • for smaller fauna, a light embankment/fill in relation to the thalwegs is recommended. • take the DIREN inventory into account. • limit land requirements.

• maintenance of ecosystems.

Identification of potential outlets.

Quantitative and qualitative inventory of resources downstream of water outlet.

Specific study to preserve the initial flow system (large number of hydraulic structures), flood levels, and to measure incidence on flood system.

Carry out systematic studies.

• bibliographic study and observation of the site (preliminary geographic model); • protection of resources; • borrowing.

• estimation of difficulties (natural hazards, cavities, apparent instability index, etc.); • evaluation of uncertainties.

• for undetected underground items: bibliographic study, POS, visit to site; • quality and thickness of arch; • if the gallery is filled in, systematic study, particularly in relation to water.

Consideration of vibration problems at the construction works stage and service stage, and problems inherent to embankment/fill solution (overload).

On compressible zone (peat, waste dump,, etc.), specific study.

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Assets


Bibliographic inventory of protected nature areas, ZICO, classified sites, archaeological sites and Natura 2000

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The optimum period for aerial reconnaissance of archaeological sites is the second fortnight in June.

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Level of study



PRELIMIN ARY STUDY

APS

Restoration


R Execute upper passages (absence of constraining clearance), particularly for agriculture.

Satisfactory landscape integration of the project, all cutting. Landscape treatment in other cases (including half-cut project solutions, halfembankment/fill for restoration).

View, noise, air

• economic and environmental studies between the cut solution and others; • noise evaluation using a calculation model, and presizing of the protection devices required; • survey of law on air in relation to traffic studies; • landscaping studies of earth mound barrier for project on natural ground and exchange devices.

• earth movement balance, transport type of material / soil; • validation of the noise calculation model by sporadic measurements (zero status prior to construction work); • increased land requirement and variation of cubic meters to be moved.

Site

• draw up exhaustive nuisance inventory; • avoid borrowing in proximity to built-up areas or areas which need crosstown links; • conduct in-depth consultation with elected members.

• economic study; • reduction and/or compensatory measures in relation to nuisances (impact studies).

An ultra-light embankment/fill solution is appropriate with respect to drainage for junctions at grade.

• legibility and visibility of this type of junction.

• maintaining the level of restoration involves an embankment/fill project over approximately 5.40 m (frequently the case in urban contexts); • an embankment/fill restoration ≤ 3 m in open country is favorable to agriculture (no clearance constraint).

• in urban areas problem of land requirement, nuisances in relation to traffic on secondary networks or exchanges; • visibility problem (road restored at the same level as a storey).

If there is no maintenance of the network under filling, make arrangements for sufficient PI to handle the networks.

• make arrangements under the embankment/fill for emergency sheathing.

Secondary roads (district roads, VC)

Habitat

Local access

Other networks


D


– 19 –

March 2007


Level of study



Rest and service area

APS

Habitat

D


R Verification of legibility and visibility conditions after landscape studies.

Legibility of traffic signing.

Zones consuming excess material for landscape development.

• on parking area for heavy goods vehicles; • noise study, particularly nocturnal noise, with respect to the environment, even in open country.

Developing a consultation policy with operators, based on land reallocation objectives for the parcels directly concerned, or retrocessions of earth to set the alignment

• mandate SAFER to constitute stocks for land reallocation for deposits or borrowings; • execute if the nature of the soil allows subvertical slopes (draw up an economic balance sheet); • structured remodeling of soils excluding land reallocation for highlighting of parcels or absorption of surpluses (linear reduction of the land reallocation).

A project in natural ground, or a light embankment/fill project will help to leave hydrogeology unmodified, limit border effects (hydromorphy, prevent the creation of patches of frost and maintain water table levels, particularly for market gardening.

• specific constructional measures specific to each impact elimination or reduction must be studied and approved: • for farming, in view of the stress a embankment/fill project would seem preferable.

Interchange

Agriculture

Forestry


Land requirement

Production


– 20 –

March 2007


Nuisance Site


• approve specific measures tending to reduce the propagation of dust from earth, lime, cement (embankment/fill, watering, type of additive, etc.); • other nuisances concern land reallocation connection work: - loss of a water point; - opening access to isolated parcels of land cut off by road; - dismantling of agricultural drainage.

– 21 –

• consideration must be given to orders with drought and the provisions of the law in relation to water (constitute water reserves); • in the absence of land reallocation, carry out a precise evaluation of the financial incidence of the work, and provide compensation by agreement. Compensation must also be paid for harvest losses in the case of the agricultural land parceling plan [PPA] must also be indemnified (see Chamber of Agriculture’s scale of rates).

March 2007


Level of study

Longitudinal section



• limitation of land requirements and surfaces to be reforested; • reduce border effects and study the effects of revealing new forest edges.

• if accesses are maintained for management of forest assets and fauna, the longitudinal section will be cut or filled: - cut in areas where the border effect is very weak and where passageways are required for larger fauna; - filled to reduce wind on tree tops, in the thalweg zone for smaller fauna.

Protection (water)

• build a drainage mechanism to separate roadway water from subsurface or surface runoff water; • waterproofing mechanism in vulnerable areas.

• higher cost of the separation device; • check capacity of outlets of the rejection zone and downstream.

Materials

• examine the overall stability of large cuttings; • examine whether lowering a water tableis necessary, and its environmental consequences; • study linear widening of land requirement in areas rich in reusable materials.

Build a large embankment/fill in the event of a shortage of good material for earthworks or roadway.

Identify sectors showing this type of anomaly. (specific anomaly investigation study).

Filling study and investigation of this solution’s environmental consequences.

• complete census studies carried out with hunting federations by gathering data from residents (to optimize the routes of paths); • this provision may be applied where clearings are crossed.

Limit clearing, offset cutting effects on assets, and close off the entire sensitive area in linear fashion.

• provision to be retained for crossing small vales and valleys; • increase the number of structures with embankments if there are rivers or other watercourses nearby.

Widen the land requirements to build high plantations on the roadway and slopes in order to clear avifauna flight levels.


TN

Forestry

Undergrou nd resources APS

Large fauna

Restoration of a regular route


R

Plant assets

Cavity

Small fauna

D

– 22 –

March 2007


Level of study



Small fauna

Flora

D


R

Grazing and water point

Ensure continuity of surface runoff from catchment areas, and create pools with gentle slopes in clearings and grazing areas.

Prevent release of water from the roadway into this substitution area.

Perpetuate established flora, and favor the establishment of new protected species.

Protected species

• prevent any occupation of land (site installations, material storage, miscellaneous work, etc.) in ecologically sensitive areas; • modify horizontal alignment if possible, in such a way as to maintain the ecosystem in specific areas (air, wind, dust, light, humidity, etc.); • carry out landscape development consistent with specific local features favoring refuge areas. • Build structures to collect surface and subsurface water and keep them in a good state of repair, from the works stage to opening to traffic ional use; • in addition to the required hydraulic structures, design drainage bases across valleys and areas liable to flooding≈.

• for top ditches: check stability of slopes and accessibility; • for subsurface water: check non-contamination of the upper parts of earthworks (PST), capping layer and roadways; • modification of the piezometric layer (risk of recession, or humidification of rejection zones).

• during the construction works stage, remove material in suspension (MES) before discharge into the natural surroundings (settling basin); • during the final stage, water treatment before rejection (settling, filtration, purification) and implementation of an accidental pollution blockage system.

• incidence on spawning areas of migratory fish, and pollution of water tables in karstic presence; • in vulnerable areas (tapping in suboutcrop water tables, etc.), total roadway proofing.

APS

Internal water and surface runoff

Water

Roadway runoff



– 23 –

March 2007


Level of study



Landscape

APS

Soil

Air

Integration of the project

Reutilization

Pollution

Scheduled site Assets

Archaeology


D



• determine landscape sequences and positive points to be retained; • blend the project into the landscape, with no particular emphasis (unless the project is a structural feature of the landscape); • landscape treatment of borrowings or deposits; • consideration of maintenance in the design; • study solutions involving viaducts or embankments/fills in sensitive areas.

• uniform interpretation of land reallocation with the landscape architect (specifications); • basic principles: - choice of embankment/fill heights; - choice of cut depths; - type of slope gradient; - treatment of transitions (natural ground/cuts/embankments /fills); - modeling of slopes in terms of natural image; - planting of earthworks slopes. • accessibility of remote areas. • environmental and financial consequences.

• carry out geotechnical level studies; • make a list of availabilities and needs in areas of vegetation and temporary and final deposit areas; • carry out specific studies in compressible and/or unstable areas to investigate natural deposits on specific fillings, due to underground components, cavities, etc.

• soil nature quantification of materials which are reusable for roadworks, for the environment (landscape) and for agriculture (soil restoration); • earth movements and soil treatment technicality; • suitability of soil types and treatment for the landscaping project.

R

Placing the project in Constitute an air quality cuttings and providing zero condition prior to hedges at organic crops; work. hospitals, retirement homes, schools, etc., located in prevailing winds will reduce atmospheric pollution. Based on horizontal alignment, longitudinal section and a landscape sketch, refer to Architectes des Bâtiments de France (ABF) for special authorization and opinion.

• in-depth study in the event of co-visibility and crossing of protection area (500 m strip); • preliminary statement for licensed sites.

No geological boring or excavation at sites rich in archaeological features.

Prior action by DRAC for site investigation (cost and timelines +++).

– 24 –

March 2007


Level of study



D


R

ZNIEFF

Reduce land requirements and carry out all studies requested by DIREN within the context of the circular of 19 September 1999.

In accordance with the results of surveys, more or less specific measures must be taken.

Natura 2000

Cut or embankment/fill solutions may be reversed in accordance with objectives to be retained. A viaduct may sometimes be the solution for crossing a valley listed in a Natura 2000 area.

Care must be taken with land requirements. It is occasionally necessary to compensate the disturbed surface area by acquiring 1/5 or even 1/10 additional area.

Restoration

• preferably carry out a cutting project and overpasses at natural ground level, or fillings for restoration work (unlimited road gauge for restoration); • in an underpass hypothesis, examine drainage on the lane restored; • avoid curves and reverse curves in overpass embankments/fills.

• create models of earthworks slopes with gentle gradients for integrating road restoration projects into the landscape; • favorable incidence on noise reduction (screen perpendicular to the project); • legibility and visibility of restoration. • possibility of integrating independent routes for pedestrians and cyclists; • space available to absorb excess.

Interchange

• improved filling legibility of interchange (restoration of state highway, district road or municipality routes is on upper level); • landscape study of treatment of spaces between ramps; • better interchange drainage; • no road gauge constraints. Design of noise protection devices and measures.

Comparative study (suitability, efficiency, aesthetics, cost).

Retain techniques causing the least nuisance in terms of dust, vibrations, noise and projections.

Check that the techniques advocated or which are likely to be used by the contractor will not entail any deterioration of the built-up surroundings.

Stop borrowing and/or final deposit areas (acquisition by road project owner, and subsequently returned to area following redevelopment of the site).

Carry out parcel inquiry after public inquiry (official approval - DUP) and modification of project in accordance with the observations in this inquiry, or after the Water Act inquiry.

Assets

APS

Restoration and interchange

Noise

Habitat Site PROJECT

Agriculture



Land requirement

– 25 –

March 2007


Level of study



PROJECT

Undergrou nd resources

Land requirement

Alignment

Proceed with sporadic horizontal setting and longitudinal section on the project with respect to the observations by the public inquiry and mixed instructions.

Conduct additional studies on the project as modified in terms of soil identification (homogeneity) and drainage.

Confirm or notify the new project characteristics to the manager of forest areas to allow him to implement a cutting plan.

Loss of wood may be accounted for in purchase by the project owner. In this case, engage clearing procedure.

On the basis of the project’s geometric characteristics, conduct hydraulic studies to approve and size structures to protect surface runoff water and subsurface water.

• this type of study is to be conducted at the same time as the study required for collection and treatment of water on the road platform; • these surveys are necessary to obtain authorizations or declarations in relation to the Water Act; • all these studies, or the Water Act report, can modify initial project drainage and therefore the land requirements.

Study and sizing of overpasses for large fauna.

Determine the length of fences for large fauna that must be provided together with this overpass.

Assets management

Water protection

Fauna Small fauna


R Check access on road for construction traffic and operational nature with respect to plausible order for the operation.

Large fauna

Water


Arrangements for installation of site on road land (service or rest area), or on surface land, on a parcel which cannot be used by farmers.

Agriculture

Forestry

D


Protection

Examine all solutions above Objective: to reduce the and below the structure isolation phenomenon. which make the structure transparent with respect to small fauna. • engage all hydraulic studies in accordance with the Water Act (authorization or declaration); • size structures for collection and treatment.

– 26 –

Water is subject to special regulations. A single engineering firm should be approved for all water studies (see: underground resources + water).

March 2007


Level of study




Integration of the project

• the landscaping project, generally subcontracted to a particular construction manager, must be completed before focus of the parcel inquiry which will set the final land requirements; • the landscaping project concerns all road work and the specifications to be given to the landscape architect working on land reallocation; • consideration in the design of maintenance of plantations and green spaces (accessibility of remote areas, routes, paths, fences, road facilities, etc.)

• request assistance from the landscape architect advising the construction manager in relation to monitoring of subcontracting work; • supply the specific manager with the project, but also the geological cross sections defining nature of soils and the main outlines of the earthworks • plan on site monitoring services for preparations of tender documents [DCE] for landscaping.

Reutilization

• carry out geotechnical studies for the DCE; • carry out soil treatment studies; • carry out structurespecific geotechnical studies; • make a list of availabilities and needs in areas of vegetation (temporary and final deposits).

• adjustment of nature of soils and quantities available; • production of earth movement plan; • economic report on reutilization of soils and possible examination of the required exterior filler material.

• implement an excavation agreement with an archaeological association approved by the DRAC; • the agreement must envisage conditions for rehabilitation of soils after excavation (soil reworked, degraded, moistened).

• following excavation these soils are now unusable and entail extra costs, additions to timelines, or deficit of good material; • insist on filling conditions with the association in accordance with technical rules, or arrange for filling to be carried out by a competent firm acting as construction manager.


TN

Landscape

PROJECT

Soils

Assets


Archaeology

D

R

– 27 –

March 2007


Level of study



Integration

PROJECT

Restoratio n and interchang e

Supply route


D



R • consideration of observations from the public inquiry and mixed instructions; • consideration of landscaping models and pedestrian routes in urban areas; • setting of network shifts with concessionary companies.

Ensure visibility distances are maintained.

• draw up an inventory and agree the type of restoration accepted by the construction manager for the lane concerned; • draw up an agreement with the construction manager for rehabilitation of town center links.

• site order with respect to the authorized speeds, at the site entry point; • estimation of rehabilitation work; • neighborhood discomfort by nuisances generated by heavy-goods vehicles in town centers (dust, noise, lack of security, loss of clientele in guest houses and hotels, etc.).

– 28 –

March 2007


A.4 – Earthworks at all stages of studies A.4.1.1 –Minor cuts (≤ 3 m) Structure in minor cut area (≤ 3 m)

Level of study

Point which could call into question the nature of the structure, or its feasibility

Solution Area of incidence to To be be considered studied

Presence of finely In compressible altered, changeable areas or compressible soils Reutilization of soils

X

Points to be examined Capacity.

X

Quality of the preliminary geological model.

Natural hazard – apparent instability index

Stability of embankments and earthworks slopes

X

Quality of the preliminary geological model – topography upstream hydrogeology.

Conservation of internal flows and their quality (protection of resources)

Hydrogeology

X

Suboutcrop or perched water. Protection of tappings well etc Waterproofed geological layer or protection Gradients of earthworks slopes. Maintenance of ecosystems (biological corridor).

Stability of slopes

X

Supply of protected areas

X

Leisure habitat Landscape Natural surroundings Agricultural land requirement

X X X X

Noise protection Landscape sequence / resident / user Maintenance of ecosystems

Preservation of forestry assets

Land requirement – Flora hydrogeology

X

Absence of earth mound barrier, deposits, etc.

Special structure for large fauna

Large fauna

X

Special overpasses for large fauna and closure upstream and downstream.

Earth movement principle

Project savings

X

Examination of large masses.

Assets – landscape integration

PS

To be avoided

Suboutcrop water Water resource table Hydraulic structural area liable to flooding damage

X

Proofing of the road platform Lowering of water table, instability.

X

Project drainage

Agricultural parcel drained

X

Restoration of agricultural drainage rejection.

Noise

Habitat

X

Land requirement, restoration - special structures. Mining, vibration, compacting.

Minimum land requirement research Restoration of state highways, district roads and VC’ in PS


Agriculture forestry Habitat (urban)

X

Subvertical earthworks slopes.

X

Covering the lane.

Land requirement on secondary road Agriculture (gauge) Landscape

X

Feasibility in urban areas, access.

X X

Structure for agricultural access Land requirement.

– 29 –

March 2007


Structure in minor cut area (≤ 3 m)

Level of study

Point which could call into question the nature of the structure, or its feasibility Isolation of large fauna (overpass)

Solution Area of incidence to To be be considered studied Closure upstream and downstream of overpass. Cost

Material resources

Capping layer and roadway

To be avoided

X

Additional land requirement on wooded spaces.

X X

PS Agriculture

APS

Points to be examined

X

Quarries or materials in the land requirement The economic and environmental aspect with respect to natural deposits available excluding land requirements Large single tracts of farmland.

Detected underground Quality of arch (risk cavity which can be of collapse) inspected (man-made or natural underground cavity)

X

Stability of arch during the construction work and service stages. Research into archives (district, municipality, geological and topographic maps). Analysis of vertical aerial photographs by National Geographic Institute (IGN) Survey of the site and oral inquiry.

Identification and Alignment – earth method for balance reutilization of soils (quality of the geological model) Climatic conditions

X

Quality of geotechnical studies (positioning, depth and number of bores - timelines – accessibility of parcels, etc.).

X

Quality of materials

X

% reutilization. Execution timelines Changeable nature of materials. Treatment. Mining. Cavities. Compressible areas. Suitability for the landscaping project. Sloping.

Measurement (economic report)

Earth movement

Earthworks

X

Special structures

X

Project savings

X

Considerable imbalance Deposits

Trafficability, changeable materials. X

X

Earth mound barrier


Earth balance. Shortfall of materials - surplus of materials. Drainage blanket shields etc Structures (bridge, viaduct, tunnel, retaining wall, etc.).

Drainage – landscape consistency. Landscape integration.

Borrowing or surplus

X

Site pollution

X

– 30 –

Rest area, service area or outside land requirement Width of land requirement (to be defined in the official approval report (DUP) Dust (soil-binder), runoff water, noise / schedule. March 2007


Transport distance


X

– 31 –

March 2007



Level of study


Solution Area of incidence to To be To be be considered studied avoided

Problem relating to bearing capacity (nature of subsoil and water)

Thickness and quality of the upper parts of earthworks

Shortage of reusable materials (even after treatment of soil)

Widening of land requirements (in open country)

X

X

Widening of land requirements (in i h bit d ) Sl

Reduction in l it di l

(

i

t

X

Hydraulic environment.

)

X

Administrative procedure for opening up quarry, landscaping, cross-town link. Public inquiry on classified facilities and public inquiry on project in such a way as not to call into question the technical and financial feasibility of the operation). Check that the natural deposit’s quantity and quality meet the requirements.

Increase in heavygoods vehicles

X

Landscape integration.

Noise protection

X

Compatibility of materials with plantations. Stability of earth mound barriers with t t t

T

X

T h i l

Exchangers, leisure areas, private t

X

Landscape consistency of filling in of grade separations (restoration to i lt )

Deposits outside land requirement

X

Conformity with administrative procedures (public inquiry) for landscape integration (law on waste).

L

d

X

C

L

d

X

C t/

X

DIREN agreement.

X

Geometry.

t

t f

i

Reception i t (fl Earth balance


thi t

ti

APS

Addition to deposits, earth mound barrier

Stability of environmental structures. Acoustic survey and type of protection. I i i i ll

X

Borrowing (excluding land requirement)

Surplus materials

Substitution. Embankment/fill.

Modification of width and/or slopes in the project. Dimension of the agricultural parcel (if large operations are to be avoided). X

i


il

t

i t

i

t

fi l

t t

ff h

t

(AF)

)

– 32 –

March 2007



Level of study

Point which could call into question the nature of the structure, or its feasibility Quality of the upper parts of earthworks

Solution Area of incidence to To be To be be considered studied avoided Earth balance


X

Accuracy of geotechnical study. Lasting durability during the construction works stage.

Substitution

X

Nature, thickness and quality of materials.

Long-term durability of the upper parts of earthworks

Drainage

X

The upper parts of earthworks must not constitute a water trap.

Capping layer

Earth balance

X

Accuracy of geotechnical study (additional bores for treatment aptitude test). Reutilization (treated or untreated), borrowing quarry Technical-economic report (capping layer [CF]-roadway).

Resources in materials

X

Hydrogeological context

Drainage

X

Drainage / constructional measures. Separate sewerage system.

Lowering of water table and miscellaneous hydrogeological modifications

Site phasing

X

Technique site preparation

Urban Agriculture (market gardening)

X X

APS Forestry Project drainage & sewerage

Construction works stage In service (separate sewerage system) Agricultural parcel drained

X X

Construction works stage Underground gallery – Stability of unit natural or man-made cavity


Water Act, temporary basin, stability of earthworks slopes and protection of tappings wells trafficability Water Act, drainage - flow Runoff in catchment areas (top ditch) Restoration of agricultural drainage rejection.

X X

Protected tapping area Water resource

X X X

– 33 –

Stability of surrounding built-up structures Area of influence, separate sewerage system. Border effects (hydromorphy). Dismantlement of agricultural drainage Area of influence.

Downstream hydraulic positioning of project Proofing, collection and rejection outside perimeters. Specific research study into anomalies – bores and/or microgravimetry, volume concerned. Shaft or camera inspection with regard to quality, thickness and stability of covering arch. Behavior when subject to vibrations. Circulation of subsurface water. Techniques for embankment/fill, effect on natural surroundings. Protection dyke for swallow-hole areas, waterproofing of ditches and bottom of basin.

March 2007



Level of study

Point which could call into question the nature of the structure, or its feasibility Cut in aquifer environment (see singular point)

Solution Area of incidence to To be be considered studied


Drainage of the platform

X

Stability of earthworks slopes, of the upper parts of earthworks and sizing of the drainage network.

Upper earthworks platform Maintaining the balances

X

Determine the technique.

X

Evaluate the area of influence and carry out systematic studies in the “disturbed” area.

Caution with sloping: a slope becomes an obstacle at certain gradients

Short and long term stability

X

Variable slopes, support, gullying/drainage substitution, berms, subsurface water, fine soil, safety.

Sloping

Balance of earth

X

Presence of good material off the platform. Modulation of land requirements Geometry (drawing up a more natural and less artificial image), withdrawal from risk areas cost Earthworks slopes with gentle gradients (= 3H/1V) Reduction of surfaces to be maintained and accessibility (in the absence of plantation) Safety / Geometry.

Landscaping

X

Planting Operation Maintenance

APS

To be avoided

Blasting rock excavation

Site nuisance Geotechnical study Assets

Landscape development

Sloping

Plantations

Land requirement for Forestry wooded areas and Fauna sensitive agricultural areas

X

X X X

Vibrations and noise protection. Deterioration on constructions Characterization of rocky area Subjection to protection of structures.

X

Consistency in interpretation of landscape for users and residents (geomorphology).

X

Compatibility of the nature of soils with the type of plantations. Reduction of snowdrifts (hedges).

X X

Limitation of the land requirement Specific study of passage points and grazing areas. Preferably an overpass for large fauna. (care to be taken with the hump effect / road gauge) The location and the quality of the surroundings to be preserved for protected species

Flora

X

Winemaking

X

Restoration of state Urban highways, district roads and municipality routes on overpass.


X

X

– 34 –

Legibility and visibility of junctions.

March 2007



Level of study

APS

Point which could call into question the nature of the structure, or its feasibility Atmospheric pollution (dust from earth, lime, treatment, air law)

Solution Area of incidence to be considered

Urban

S

ifi

i

lt

Points to be examined Presence of a sensitive environment (hospital, school, retirement home, car parks).

X

O

X

Maintenance of ecosystems as of the construction works stage.

Dense habitat (urban)

X

i

k t

d

i

t

Land requirement – tendency towards mineral structures.

Suburbs

X

Land requirement.

Earth balance

X

Reduction of soil excess Fewer materials available – a deficit.

Landscaping

X

Increased land requirement for nonclassical shapes.

Habitat - Agriculture

X

Location and layout of the site installation, processing units and binder and lime silos.

Earth movement

X

Work phasing (earth mound barriers to b t d fi t)

Site road

X

Land requirement, location and layout of the site road, interference with general traffic.

Borrowing outside land requirement authorized by quarry openings (law of 19/07/76)

All areas, including utilization of existing lanes

X

Examination of transport routes (public highway or site road). Temporary occupation agreement and/or agreement for rehabilitation with the route project owners. Evaluation of costs.

Excess material

Reduction of land

X

Stability of earthworks slopes if they

Longitudinal section (heavy goods vehicles)

X

Increase in heavy goods vehicles in areas with materials of poorer quality. Landscape integration of restorations (taller and longer). Noise protection in built-up area. L i t fd i

Deposits environment

X

Growth of land requirement. Increase in landscape noise protection. Landscape integration of deposits. Projects of general interest for t it i l

Earth movement

X

Movement balance with respect to the plausible phasings and allotment. Work schedule constraint (implementation of structures).

Nuisances

PROJECT

To be avoided

X

Flora Noise protection earth mound barriers

To be studied

Transport distance in the land requirement


– 35 –

March 2007



Level of study

Point which could call into question the nature of the structure, or its feasibility Very large deposit outside land requirement


To be studied

To be avoided

Agriculture

X

Specifications for depositing process on agricultural parcels. Validation and evaluation of costs by district-level offices for agriculture (DDA) and chamber of agriculture (CA). Compatibility of the process with the procedure for classification of land reallocation areas.

Quarry, miscellaneous excavations

X

Conformity with quarry redevelopment plan. Authorization by the Préfet or statement. Evaluation of costs.

Forestry

X

Biological corridors.

Deterioration of borrowed roads

X

Examination of transport routes. Roads rehabilitation agreement with project owners. Evaluation of costs.

Landscape

X

Landscape study of each particular case with respect to the excess amounts. Land requirement, location and layout of the site road, interference with general traffic.

Forestry

X

Clearing procedures after examination of cutting plans in forestry operations.

Archaeology

X

Reworking of soils at archaeological excavations (increased water content, heterogeneity of soils in place, d ti i titi il bl t )

Earth balance

X

Stump extraction and archaeology often involve loss of materials due to d t i ti f i t i it

PROJECT

Clearance of land requirements

Networks



X

– 36 –

Investigation beyond the classic networks (water, electricity, gas, etc.), including outside the land requirement (150 m on both sides of the axis) into the existence of special networks of pipelines, gas lines and optic fiber, and examine the problems of safety, timelines and cost of travel.

March 2007



Level of study



Reutilization of soils

Alignment Earth balance

X

Quality of detailed geotechnical studies. (positioning, depth and quantity of bores – timelines – accessibility of parcels, etc.). Pertinence of % reutilization of materials with respect to all constraints, particularly climatic constraints, in the geotechnical study. Study of slope stability. Implement geotechnical studies at project level – extremely detailed information for risk areas.

Archaeology

X

Loss of reusable materials due to contamination of materials and increase in water content (earth balance).

Plan of earth movement

X

Determination of functional phases (allotment of future contracts). Management of deposits and borrowings. Adaptation of climatic periods to sensitivity of locations.

Capping layer

X

Characterization of natural deposits in the geotechnical study. Specific soil aptitude study. Formulation study for treated soils. Test site if the material is mishandled. Technical-economic sizing (capping layer/road).

Economic evaluation

X

Evaluation of overall cost with integration of the environment.

Landscape

X

Reutilization of unfit soil excluding main structure (landscape embankments/fills, earth mound barrier, etc.). Reduction of all slope gradients. Tendency to round shapes. Management of reutilization of plantation areas / soils.

Nuisances

X

Use of explosives. Wave propagation study, monitoring of operations. Acquisition of property, reinforcement of building.

Material resources

X

Reutilization on earthworks and / or on roads. I t f h d t i l f ilit

Sloping against falling rocky blocks

X

To be studied

PROJECT

Rocky soils


– 37 –

To be avoided


March 2007



Level of study

Point which could call into question the nature of the structure, or its feasibility Drainage


To be studied


Underground resources

X

Size the subsurface water drainage network (quality of the geotechnical study). In karstic areas, study the water routing (karst resupply or dewatering). Study of phasing and compatibility of drainage with earthworks stages. Restoration and maintenance of ecosystems. Impact report in relation to the Water Act.

Order and stage of work

X

Non-contamination of soil by arrival of water.

X

Due to variations in water content, implement a more in-depth moisture study to measure extreme Ws simultaneously with geotechnical studies at project level. Implement a soil treatment study (% of soil to be treated – cost of treatment).

Overall stability

X

Reactivation of large old slides in the event of inappropriate water losses. Destabilization of slope (problem relating to dip and/or fine clay-shale layers). Protection of slopes from runoff water.

Water from road platform

X

Width of platform. Impact report in relation to the Water Act. Operation of drainage systems.

Construction works stage

X

Earth runoff water – pollution in streams – settling of material in suspension (MES) prior to rejection. Potential falls in bearing capacity with regard to poor design of site drainage.

Fauna

X

The longitudinal section of the large fauna route. 7 - 8 m embankments/fills are better suited to the natural ground continuity for large fauna.

Earth balance

PROJECT

Overpass for large fauna

To be avoided

A.4.1.2 –Minor embankments & fills (≤ 3 m) Structure in minor embankment/fill area (≤ 3 m) Level of

Point which could


Area of incidence to

Solution

– 38 –

March 2007


To be studied

Noise nuisances Landscape

Restoration of routes intercepted at underpasses

Habitat

Habitat

X

X

Agriculture

Landscape integration Leisure habitat - Assets Landscape

PS

X

Sequence: landscape / residents / users Maintenance of ecosystems

X

Earth movement principle

Project savings

X

Underground water resources

Absence of earth mound barriers, deposits, etc. X

X

Suboutcrop water table Water resource – area liable to flooding Modification of natural flows

Land requirement on secondary road and resident access. Stability of residents’ property Road gauge limited to height 4.25 m (compatibility of agricultural equipment and mobile machinery with underpass opening and gauge). Noise protection

Agricultural land requirement

Large fauna

Extra land requirement for equipment and landscaping. Protective structure on embankment/fill (technical-economic study). Sloping or support.

X X

Special structure for large fauna


X

Natural surroundings

Conservation of forest Land requirement – assets hydrogeology of flora

To be avoided

Compatibility of heights/altitudes. Compliance with natural route. Examination of large masses.

X

Waterproofing of the platform. Lowering of water table, instability.

X

Inventory of potential settlement areas.

X

Identification of the nature of the bearing soil and layers in presence. Examination of the incidence of the project with regard to flooding.

Karstic area with Soil plausible underground

X

Bibliographical inventory, feasibility of examination of the quality of the arch, site survey.

Compressible area

Soil

X

Nature and thickness of soils in place. Road project feasibility study.

Polluted area

Waste dump

X

Bibliographical inventory (Town Hall, DRIRE, DASS) and on-site investigation. Road project feasibility study


Evolutional materials Noise nuisance APS


X

Urban habitat Habitat in open country

X X

– 39 –

Sizing of protection structures. Sizing of earth mound barriers for protection (significant widening of land requirement).

March 2007


Structure in minor embankment/fill area (≤ 3 m) Point which could call into question the Level of nature of the study structure, or its feasibility


To be To be studied avoided

Restoration of routes Habitat intercepted at underpasses

X

Points to be examined Access to resident parcels. Pedestrian route. System to remove water from road (safety).

Drained agricultural parcels

Agriculture

X

Carry out an agricultural compartment history collection. Continuity of the system and outlets under embankments/fills (subsurface water = separate sewerage system).

Excess materials

Widening of land requirement (in open country)

X

Modification of project slopes and/or width. Agricultural compartment history (if

Widening of land requirement (in i h bit d )

X

Development of service areas, rest areas and interchanges

X

Increased surface for areas consuming ills. HGV parking isolation at service areas by landscape earth barriers. Sloping on mild slopes for all t t

Earth barrier for noise protection

X

Accessibility for maintenance of landscaping spaces.

Sloping

X

(see this topic below)

Reduction in longitudinal section

X

The hydraulic environment, road gauges and gauges on routes operated b i lt

APS

Deficit of reusable materials (even after treatment of soils)

Borrowing (excluding land requirement)

Measurement (economic evaluation)


Stability of environmental structures. Acoustic study and type of protection. I i i i ll

X

Administrative procedure for opening up quarries, landscaping, cross-town link. Public inquiry for facilities classified with IMEC and public inquiry for the project so as not to call the technical and economic feasibility of the operation into question. Check the quantity and quality of the deposit match the needs.

Earthworks

X

Earth balance. Deficit of materials. Excess of materials.

Special structures

X

Structures (bridge, viaduct, tunnel, retaining wall, etc.).

– 40 –

March 2007


Structure in minor embankment/fill area (≤ 3 m) Point which could call into question the Level of nature of the study structure, or its feasibility

APS

Modification of air and water flows



To be studied

To be avoided


Agriculture

X

Limit border effects (hydromorphy). Prevent creation of patches of frost. Market gardening culture / air pollution.

Water resources

X

Choice of systems to restore internal flows (separate sewerage system). Supply of natural environments and maintenance of existing balances. Evaluation of settlement in bearing soils. Stability of earthworks slopes and accessibility for monitoring and maintenance of toe ditches for water from road platform or catchment area. Check non-contamination of the upper parts of earthworks (PST). Silting up of the internal network and its restoration. D i f h id


X

Suppression or reduction of the area liable to flooding. Work on the ditch network (land reallocation) and creation of outlet (pond). Maintenance of ecosystems and the area liable to flooding. Sizing of the permeability of the embankment/fill and hydraulic structures for conservation and nonaggravation of the area liable to flooding. Overall stability study. Protection of earthworks slopes ( k )

Water from road platform

X

Treatment and balancing reservoir. Natural outlet. Percolation basin (cover/water table) Protection of drinking water supply [AEP] tapping and others.

– 41 –

March 2007


Treatment of water from the road

Drainage (reception environment)

X

Before any water percolation, examine and draw up vulnerability charter for soils / at water tables. Outside ecologically sensitive areas or areas which are vulnerable with respect to underground resources, favor diffusion of water from the road platform at a large number of rejection points. Concrete structures on vulnerable zones only. Cover between the bottom of the percolation basin and water table layer.

Structure in minor embankment/fill area (≤ 3 m) Point which could Level of call into question the nature of the study structure, or its feasibility Karstic zone and underground gallery


To be studied

Soil

X

Quantify geological anomalies or underground mine areas. Overall stability study. Geological incidence of the solutions approved. Light embankment/fill.

W t

X

P ll ti

Drainage

X

Maintenance of natural water circulation. Waterproofing of the area with regard to water from the planned road.

All fauna

X

Precise inventory of species and passageways towards grazing areas.

APS

Biological corridor

Earth movement


To be avoided


f

t

t bl

Small fauna (special X structures)

Sizing of structures for small fauna (duct ∅ 400, 1000...). Opening of hydraulic structures (with ti f t b k t )

Longitudinal section X (earth balance)

Heavy goods vehicle constraint in due consideration of structural cover for the project to be implemented on the t t f ll f

Avifauna (land requirement)

X

Widening of the road platform for plantations at top of embankment/fill (ecological thalweg area).

Balance, economic evaluation Borrowing or deposit

X

Study of large masses of earth movement (examine extreme solutions with regard to weather conditions). Choice of materials for the capping layer (materials from the site or quarries).

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March 2007


Compressible or polluted area

Embankment/fill on transversal slope (> 15% or less in certain cases)

Soil

X

Detailed geotechnical investigation. Specific study of runoff water and gas in the polluted area. St d f t bilit d ttl t

Filling technique

X

Embankment/fill construction method in compressible or polluted area. Filling technique (classic, heterogeneous, composite). Incidence on the environment / occupation of land.

Overall stability

X

Detailed geological investigation of the site. Presence of fossil sliding. The block’s hydraulic conditions. Potential seismic activity. Overall stability study.

Construction - Site

X

Embankment/fill construction method. Stability during the construction stage. Constructional measures at the construction works stage (sizing and fi i l i id )

Structure in minor embankment/fill area (≤ 3 m)

Level of study

APS



Sloping of 3h/2v 5 h/1v and more

Integration into landscape

N.B. with certain Stability gradients, a slope becomes an obstacle Operation Maintenance

PROJECT

Clearance of land requirements


Forestry

To be studied

To be avoided


X

The earth balance for all types of slope. If there is an excess of materials, tendency towards landscaped slopes (a more natural image).

X

Gentle slope if there is fine soil or planting. For bleachable soil, slope must be vertical or extremely flat Bush plantation in inaccessible areas. Restitution to agriculture.

X X

Clearing procedures after examination of the cutting plans for forest operations.

Polluted areas

X

Topsoil

X

Archaeology

X

Treat these areas within the context of waste legislation Pedagogical study of topsoil. Qualitative and quantitative evaluation. Choice of areas to be coated with topsoil (slope in the case of plantations) Reworking of soils at archaeological excavations (increased water content, heterogeneity of soils in place, bearing capacity, etc.)

– 43 –

March 2007


Noise nuisance

Maintenance of demolished structures

X

Structures to be evacuated

X

Earth balance

X

Networks

X

Drainage, irrigation

X

Dense habitat (urban) Suburban and open country

Homogenization of materials in place with regard to the bearing capacity of the platform supporting the embankment/fill. Circulation of water vertically between the body of the embankment/fill and the demolished structure. Adhesion of the embankment/fill on smooth surfaces (overall stability) Recycling of products of demolition and / or evacuation (with respect to legislation on waste) Stump extraction and archaeology often involve loss of materials due to deterioration of environments in situ Movement of networks and problems relating to safety and gauge in the presence of boundary networks or networks which have not moved Temporary restoration, pending work in relation to land reallocation, drainage mechanisms and mechanisms for agricultural irrigation. Site flooding risks. X

X

Land requirement and stability of noise protection walls Widening of the platform for protective earth mound barriers on the embankment or screens. Landscape integration. Earth balance.

Structure in minor embankment area (≤ 3 m)

Level of study

PROJECT



To be studied

To be avoided


Noise nuisance


X

Transport of materials on urban site, tourism.

Borrowing outside land requirement authorized for opening of quarries (law of 19/07/76)

All areas, including use of existing routes

X

Examination of transport routes. Temporary occupation agreement and/or agreement for rehabilitation with the project owners for the routes. Evaluation of costs.

Excess materials

Increase in land requirements

X

Landscaped embankments/fills (gentler slopes), restitution to agriculture,


X

Increased longitudinal section (compatibility with landscape integration and drainage).


– 44 –

March 2007


Deposits environment

X

Increased land requirement. Landscape integration of deposits. Improvement of landscape noise protection. Projects of general interest for territorial groups. Reduction of embankment/fill slope gradients.

Earth movement

Balance, economic evaluation Borrowing or deposit

X

Detailed study of the earth movement plan. Examination of extreme solutions in terms of meteorological conditions.

Sloping

Land requirement limited

X

Retaining wall or vertical sloping, even 1/1 (difficult or urban site).

Landscaping and land requirement

X

Landscaping models to create a landscape. Landscape embankments/fills ( tit ti t i lt )

Geometry

X

Stability of earthworks slopes with respect to the quality of materials implemented, abutments, erosion and road runoff. Adaptation of accessibility and safety for maintenance.

General stability of the structure and its support

X

Unstable and/or changeable materials (sensitivity to moisture changes). Unstable bearing soils (compressible area). The suitability of soils for treatment. The homogeneity of the body of the embankment/fill. The inverted order of the layers extracted and implemented (compatibility with their positions in the body of the embankment/fill).

Reutilization of soils

Structure in minor embankment/fill area (≤ 3 m)

Level of study

PROJECT

Point which could call into question the nature of the structure, or its feasibility Quality of the upper parts of earthworks (PST)



To be studied

Bearing capacity

X

– 45 –

To be avoided

Points to be examined Substitution of materials of insufficient quality. Drainage of humid areas and tapping of resurgences. Air-slaked lime treatment or treatment with binders of materials in place.

March 2007


Water resource

Drainage

Karstic area, with underground components


Nature and quality of reutilizations

X

The quantity of materials available. The mechanical performances of materials. Treatment of materials. Economic evaluation of the combined upper parts of earthworks / capping layer [PST/C]. Form/Road by homogenous upper parts of earthworks / capping layer [PST/CF] sections.

Drinking water supply [AEP] tapping

X

Compression of bearing soils and modifications of internal flows.

Surface runoff

X

Hydromorphy of contiguous areas on the embankment/fill. Absence of outlet and creation of fl d d f

Area liable to fl di

X

Higher flood levels.


X

Identification of the sampling points. Management of authorizations for sampling and rejection. Compatibility of the device in view of drought orders.

Order of stages

X

Non-contamination at foot of embankment/fill by arrival of water.

Stability of the structure

X

Dissipation of interstitial pressures in the bearing soil.

Cross section of the earthwork platform

X

Evacuation of runoff water from the embankment/fill surface (V or W profile is a favorable factor in terms of quality of compaction and safety at the t ti k t )

Stability of earthworks slopes with respect to gullying

X

Creation of gutter and collection of water in prefab drainage channels.

Reception environment

X

Temporary settling structures for site water prior to rejection (care must be taken with fish reproduction periods).

Environment – Stability of structures

X

Precise definition of constructional measures from the point of view of the environment and from the point of view of the construction works stage, with regard to stability and safety on the site and during service.

– 46 –

March 2007


A.4.3 – Large embankments/fills (> 3 m) For large embankments/fills (> 3m), at all level of studies an examination must be made of all the points covered in tables concerning embankments/fills ≤ 3m, but there must also be an in-depth examination of the following points in particular which could call into question the structure’s feasibility: 1) the existence of a protected area for tapping of Drinking Water Supply (AEP); 2) presence of a water table (depth, thickness and quality of cover, pollution, lowering of the water table, etc.); 3) presence of a karstic zone (detection of anomalies and treatment of cavities); 4) presence of a compressible area (thickness, stability, substitution, economic evaluation); 5) stability of earthworks slopes and natural slopes, and the deformability required with respect to utilization; 6) environmental balance of areas (landscape, subsurface water, avifauna); 7) the need to drain major internal flows and evacuate towards natural outlets; 8) geometry compatible with maintenance (slope with a very slight gradient 1v/3h, unless there is excess material, in which case the slopes will have an gradient compatible with the stability of the soils in place and well-drained bench terraces on the slope, quality of slope edges, constructional measures at the construction works stage and in the presence of rocky materials. Sloping may follow the sites of stone traps. We should not forget to make arrangements for access to the bench terraces, stone traps, etc.); 9) incidence on structures on overpasses (height of piers).

A.4.4 – Large tall embankments/fills For major embankments/fills (>3m) which are also tall (>15m), we will have to examine, at all levels of study, all the points set out in the tables in reference to embankments/fills ≤ 3 m, but also carry out a special in-depth examination of the following points, which could call into question the structure’s feasibility: 1) the mechanical and hydraulic behavior of the bearing soil (fine soil, changeable soil, compressible soil); 2) construction of the entire embankment/fill in homogenous material (identification and quantification of available homogenous materials). A heterogeneous structure shows a risk of accumulation of water; 3) the stability of the structure in general and on particularly unstable slopes or in karstic areas and the deformability required with respect to utilization; 4) bearing soil stabilization technique; 5) construction of stabilization bench terraces adjoining the main structure; 6) environmental balance of areas (landscape, subsurface water, avifauna); 7) geometry compatible with maintenance (slope with a very slight gradient 1v/3h, unless there is excess material, and in this case the slopes will have an gradient compatible with the stability of the soils in place and well-drained bench terraces on the slope, quality of slope edges, constructional measures at the construction works stage and in the presence of rocky materials. Sloping may follow the sites of stone traps. We should not forget to make arrangements for access to the bench terraces, temporary stone traps, etc.); 8) incidence on structures on underpasses, with regard to height of embankments/fills.


– 47 –

March 2007


A.5 - Measurements A.5.1 - Definition When the horizontal axis, longitudinal section and cross sections have been established, we have all the data required for earth measurements. The purpose of earth measurement is to evaluate the cube of earthworks between skew surfaces delimiting the natural terrain and regulated, skew or flat surfaces which define the project.

A.5.2 – Basic factors used for calculation A lane of traffic is defined by its horizontal alignment, its longitudinal section and its cross sections. • the axis of the route is a space curve, and projection of this curve on a horizontal plane gives the horizontal alignment where the axis is shown as a succession of curves (circles, clothoid curves) and straight sections; • longitudinal section is the section of the project and the ground along the vertical surface which passes through the horizontal alignment. The line of the natural terrain appears on this longitudinal section. The line is shown on a plan of contour lines, on the ground, or as a spread of points plotted by a surveyor and recorded in computer files. This line is defined by points and is presented as a broken line. The longitudinal section of the project is a continuous line, generally constituted by slopes and ramps and parabolas. This line runs alternatively above and below the line representing the ground, depending on whether the project is embankment/fill or cut. The points of intersection of the two lines are passage points of the longitudinal section. The longitudinal section gives an idea of the shape of the cuts and embankments/fills, but the volumes will be well defined for the purposes of a calculation only if the cross sections are also known. These are transversal sections perpendicular to the axis. As on the longitudinal section, we find the alignment of the natural terrain and the project cross section. Cross sections are always perpendicular to the horizontal axis.

A.5.3 – Basic formula for measurement calculations (the two-surface average method) We calculate surfaces S1 and S2 of cross sections between two successive profiles P1 and P2 from the longitudinal section. We calculate the arithmetic mean of these two surfaces and apply it to length d between the two profiles P1 and P2. V = d/2(S1+S2) The accuracy obtained is around 1 – 2%.

A.5.3.1 – Classic method for surface calculation We determine the cut and embankment/fill surfaces by decomposing them into simple basic surfaces (triangles, trapeziums, rectangles).

A.5.3.2 – Simplified method for surface calculation We separately determine surfaces between the horizontal plane at elevation zero and: • the project line beneath the road foundation; • the natural ground line under the topsoil. We then subtract the surfaces obtained to determine the desired surface area.


– 48 –

March 2007


A.5.3.3 – Calculation of cut and embankment/fill volumes The diagram below explains the process for determining the volume in cubic meters from the surface areas previously obtained for each profile.

Ligne projet sous corps de chaussée Ligne T.N. sous terre végétale Nota: le profil PT4 (dit fictive) est, dans le cas present, affecté d’une surface de remblai après compensation dans le profil Vremblais Vdéblais

Project line under main body of road Line of natural ground under topsoil N.B.: Here profile PT4 (fictitious) has an embankment/fill surface after compensation in the profile V embankment/fill V cut

A.5.4 – Approximate methods We will quote two of the formulae based on this principle: the accuracy obtained using these 2 formulae is around 10%.

A.5.4.1 - Mr. DIHN MANE TOAN’S FORMULA 2 V = bS + ak S /L (do not use this formula on mixed profiles). A.5.4.2 - Mr. ROBIN’S FORMULA V = S (b + 2 k π) , with π = 0.4 hM where: b represents the width of the platform for embankment/fill and for cut, k is defined below in accordance with the gradient of the slopes, 2 S is the surface (in m ) between the line of natural terrain and the project line in longitudinal section, a is a coefficient between 5/4 (S triangular) and 7/6 (S laid flat). Generally taken as a = 7/6. L is the length of the section whose volume is calculated (same boundaries as surface S), hM is the greatest height of earthworks in the section considered. Principe des méthodes approchées Collection « Les outils” – Sétra

Principle of approximate methods – 49 –

March 2007


Remblais Déblais Talus à


Embankment Cut Slope

– 50 –

March 2007


A.5.5 – Computer methods Almost all measurement calculations are now carried out by computer, and there are many companies offering adaptable software. We may quote mainly: (see the table below) All software has the following properties: • design of the horizontal axis and the longitudinal section from lines, arches, circles, clothoid curves; • parameter and progression tabulation of the horizontal axis; • automatic alignment and calculation of the longitudinal section of natural ground (TN) from the project’s horizontal axis and the ground’s digital model; • parameterable automatic layout and design of cross sections across natural ground; • design of the longitudinal section from straight sections and circular and parabolic transitions; • modification of tabulation if necessary; • creation and management of semi-cross sections, types, multi-layer, with variable superelevations, cut bottom ditches; • calculation of measurements by application of semi-cross sections, types and consideration of stripping thickness; • parameterable automatic layout and design of cross sections natural ground (TN) and project; • calculation and design of the new numeric model integrating the project in natural ground (TN); • automatic design of the project’s main lines; • creation of a large number of files summarizing the results at different project design stages.

A.5.6 – Calculation method used by software The first design stage is modeling of the site generally obtained by triangulation of points and lines. This is an essential stage, leading to the creation of a digital ground model (MNT), to be used as a basis for calculation of measurements. The second stage is the creation of the project lines: as a priority, creation of the horizontal axis and longitudinal section. This method is common to all software. We thus have two modeling types: • construction of project cross sections from a tabulation (Piste, Autopiste, etc.); • construction of lines deduced from the red line, describing items on the platform, earthworks slopes and road structures (Macao, Mxroad, etc.). The third stage is actual calculation of the measurements and publishing of results.

A.5.6.1 – The Digital Ground Model The MNT (digital ground model) is a virtual representation of the natural ground for calculation of the point’s elevation (z) for all x/y coordinates. The most common form of MNT is triangulation. There are other models: skew surfaces from a quadrilateral (BDZ IGN file) and ruled surfaces obtained from interpolation between two lines (contour lines, existing carriageway verges, etc.).

Spread of points The spread of points is composed of points and lines. We must select the points and lines belonging to the natural ground, excluding points which have no altitude (municipal boundaries), but also contour lines which have often been calculated from the basic spread. We must work with the most accurate spread possible, excluding points and lines which are unrelated to the description of the ground. The spread forms the basis for, but under no circumstances constitutes an MNT (Figure 3). Software

Distributor (last known)

Covadis

Geomedia - Immeuble “La Vigie” - 20 quai Malbert – BP 50701 – 29607 Brest Cedex

Macao

A Bentley product distributed by Graphland

Mensura

Cobra Integra Finance - Rue Louis Blériot – BP75 – Forum d’Orvault – 44702 Orvault Cedex

Mx Road (ex Moss)

Bentley Système France – Cnit – BP 424 – 92053 Paris-La-Défense

Piste +

Sétra - 46 Avenue Aristide Briand – BP 100 – 92225 Bagneux Cedex


– 51 –

March 2007


Triangulation This operation consists of creating triangles by joining up points without crossing the lines. The main method used is the Delaunay triangulation method, selecting the most equilateral triangles possible. It should be noted that triangulation from the same spread of points may be different, depending on the programs used (Figure 4).

Geology Geological layers are generally defined from the ground’s longitudinal section, and this means they are not so accurate in terms of measurements. Their 3D modeling is barely recognized or not recognized at all by design tools, and more accurate assessments are often assigned to experts.

A.5.6.2 – Project modeling There are two main product families: • construction of project cross sections based on a tabulation – a traditional method, but difficult to use in the case of junctions; • construction of lines deduced from the red line, describing items on the platform, earthworks slopes and road structures – a more complex method which nevertheless obtains more accurate volume calculations.

By cross sections The planner initially defines a horizontal axis and a project longitudinal section, and then a tabulation based on equidistance or imposed sections. He then “interpolates” the cross sections by calculating points in accordance with the digital ground model (MNT) (Figure 5). He may then apply type cross sections (Figure 6). The Terrain [Ground] line represents the unstripped natural ground. The Projet [Project] line consists of carriageways and perhaps the central reservation, hard shoulders, embankments and slopes. The Assise [Earthworks Base] line represents the earthworks section prior to construction of the road structure. It is used to construct other lines. The Forme [Capping Layer] line is the intermediate line between the Earthworks Base and Project lines (this line may be used to mark out the capping layer or any other part of the road structure). The Base [Road Base] line is the intermediate line between the Capping Layer and Project lines (this line may be used to mark out the base layer or any other part of the road structure).


– 52 –

March 2007


Figure 3

Figure 4

Figure 5

Figure 6

Figure 5 Largeur gauche Largeur droite profil en travers point terrain calculé Axe du fichier projet

Left width Right width cross-section calculated point on ground Axis of project file

Figure 6 LES LIGNES Terrain naturel Décapage Projet Base Couche de forme Assise des terrassements

LINES Existing natural ground Stripping Proposed road Road base Capping layer Base of earthworks

By lines Moss or Macao use line modeling. Collection « Les outils” – Sétra

– 53 –

March 2007


A.5.6.3 – Calculation of measurements When the modeling of the project and the ground has been completed, we can calculate the measurements.

Linear and Gulden The linear method This is the classic method. Sections and widths calculated for each project profile are multiplied by the application length to obtain volumes and surfaces. The application length is taken at the project axis at the “inter-half-distance” between each profile. The Gulden method This method calculates sections and widths in classical fashion, but the application lengths differ from the lengths in the linear method. The center of gravity is calculated for each surface. The application lengths are calculated for each entity to be estimated (from the center of gravity), and take account of the radius of curvature. Where the Gulden method is used, the “Application Length” has no meaning. The Gulden method makes for better accuracy in the case of projects with considerable curvature: • alignment with a large number of small radii (mountain roads with hairpin bends, etc.); • roundabout ring, etc. (Figure 7).

A.5.7 – Example of calculation of measurements (with the assistance of M.X. WINDOWS 2.5) M.X. determines measurements between two surfaces on the basis of information on sections within a perimeter or a section boundary. The options proposed may be used to accurately determine measurements for the most complex forms of earthworks, such as motorway interchanges or quarries, but also the simplest forms such as standard motorway alignments. The measurements calculated may be stored in a model for subsequent use in earth movement analyses. There are two methods for calculation of measurements, using either parallel sections at constant and normal intervals on an axis, or sections taken at a right angle with respect to a certain line. The choice of the method to be used depends on the complexity of the problem and the accuracy required. The two methods may be complementary in the case of motorway designs: the measurements of the interchange area are determined using the parallel sections, and the measurements for the intermediate motorway, with regular section, are calculated using normal sections on a main axis or channel. When two models are requested, thus producing two sets of sections, the measurements are assumed to be positive when the existing surface (model 1 - cut) is located above the project surface (model 2 - embankment/fill). Existing surfaces and project surfaces are conventionally named in such a way that an embankment/fill is negative and a cut is positive (see figure 8).

Figure 7: Measurements, 2 calculation methods


Figure 8

– 54 –

March 2007


Figure 7 Surface remblai Surface déblai LINEAIRE “inter-demi-profil” Longueur d’application “à l’axe” Longueur d’application déblai

Fill surface Cut surface LINEAR “inter-half-profile” Length of application “on axis” Length of application of cut

Figure 8 NB : LÉGENDES DEJA EN ANGLAIS DANS LE TEXTE FRANCAIS


– 55 –

March 2007


Where stripping thicknesses are specified, they are applied to sections created from the existing surface. Measurements are determined between adjacent sections by multiplying the average surface of two successive polygons by the distance between them. If one or two sections do not exist, they are simply ignored, and the distance between the adjacent sections will be used to determine the real measurement (see figure 9). If a stripping thickness is specified, the height of the sections of the first model or of the existing surface will be reduced as a result. In the case of calculations of motorway earthworks, this method produces measurements associated with the abscissas on a reference line. Error management When perimeters are incomplete, the sections are closed off as follows: Section on the project surface (model 2) terminate in vertical lines through the extreme left-hand and extreme right-hand points, as in the section in the figure below. Sections on the existing ground (model 1) are spread out laterally (b). The closure points to the left and right of the section are located at the point of intersection between the two lines © (see figure 10 below).

Figure 9


Figure 10

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March 2007


A.5.8 – Assistance software developed by SCETAUROUTE A.5.8.1 - Introduction SCETAUROUTE has developed a series of computer tools for the study, design and monitoring of earthworks in relation to linear infrastructure projects. The software programs currently used are CUBATOR 2.4 and MASSTER 1.15 (Module d’ASSistance aux TERrassements) along with the geometric design software MACAO 5.4. The digital results may be exported to MICROSOFT Excel. The two software applications use geological data, geotechnical data and the geometry of the proposed design (plan, longitudinal section, cross sections) to produce a detailed study of the earthworks project and optimized earth movement. The characteristics and capacities of CUBATOR and MASSTER are defined as follows:

A.5.8.2 - CUBATOR CUBATOR was developed by Scetauroute’s Geotechnical and Materials Department. The function of the tool is to determine the resources and needs in terms of materials in relation to the project’s link section. The software uses a numeric geological model and a geotechnical study to produce the material resources available as generated by the geometry of the project. These resources may be expressed in accordance with the geological characteristics of the soil or by its reusable nature. The volumes extracted by earthworks are set out in accordance with the modes of extraction. CUBATOR can also be used to evaluate the needs in terms of project geometry in accordance with the geotechnical provisions as approved.

A.5.8.3 - MASSTER MASSTER was developed by Scetauroute’s Computer Department. Its function is to use the data provided by CUBATOR (manual acquisition from the quantity surveys is possible) to draw up the list of resources / needs by reutilization mode and to finalize studies by producing Lalanne drawings and earth movements. During the works stage, the software can re-update the study by adding the new data obtained from the complementary bores in the earthworks contract. MASSTER provides a more accurate analysis of resources. The materials are defined in accordance with their geotechnical characteristics: reutilization and presence level, yield coefficients, modes of extraction and possible treatment, nature of reutilization. Volumes of cuts, volumes and nature of the requirements are obtained per earthworks unit in relation to the link section, additional structures, restoration of communications or interchanges. The results obtained are EQVR and geometric volumes, in accordance with the nature of the materials and the forms or means of their re-use. MASSTER also helps monitor the work being carried out, providing a comparison of earth movements as planned in studies and the movements envisaged for actual construction work. It can also provide a daily update of “jobs remaining” in relation to earth movement.


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March 2007


A.5.8.4 - Conclusion in relation to CUBATOR and MASSTER CUBATOR and MASSTER, in conjunction with MACAO, are two complementary assistants to precise studies for earthworks and optimization of projects. They provide a rapid understanding of the impact of different geometric and geotechnical options on earth movements. Both of them are continually improved and upgraded, and a module for presentation of earth movements is currently being examined. Summary of CUBATOR 's functions INPUT

RESULTS

Geological data - Bores - Geological profiles on project cross sections - Nature of the materials (extraction, thickness, etc.)

---> --->

Geometric data - Reference alignment: longitudinal section / cross section (Macao file) - List of earthworks structures

CUBATOR

--->

---> Modeling - Parametering of constructional measures (upper parts of earthworks, drain base, facings, etc.) - Simple lithology modeling (nature of materials, height of explosion, etc.)


--->

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March 2007


Summary of CUBATOR 's functions

RESULTS FORMAT OF OUTPUTS Spreadsheets - Volume of resources (by nature of materials, by mode of extraction) - Volume of constructional measures Cross sections for display of volumes calculated -

Stripping of topsoil Ordinary embankment Cut Upper parts of earthworks Drainage shield Facing Earth mound barrier Embankment base Bench terrace Purge Lithological layers


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March 2007


Summary of MASSTER 's functions INPUT

RESULTS

General data - Currency - Types of structures - Transport shop

Evaluation of resources Needs

---> --->

- Evaluation per type of reutilization - Lalanne drawings

Geometric data - Definition of earthworks structures - Measurement by cross section (source MACAO)

---> Earth movement Studies

MASSTER

--->

Geological data -

Nature of the materials Characteristics of soils: Reutilization coefficient Yield coefficient Density Mode of extraction Mode of treatment Types of reutilization

- Generating earth movements in accordance with different scenarios and movements imposed or carried out

--->

Earth movement Work Geotechnical data

---> - Quantity of resources by structures - Quantity of needs / structures


--->

– 60 –

- Comparison of progress of earth movement with reference earth movement - Simulating the remainder to be carried out in accordance with reference earth movement

March 2007


Summary of MASSTER 's functions RESULTS Spreadsheets Resources by structures

Cas

Yield %

Rem. %

Total vol.

Geo. vol.

EQV R Vol.

0

3

90

4

410

16

15

1

3

90

16

410

66

59

Str. N°

Structure

Mat N°

Material

Extract

Util

5355

SC 05355

11

Silt

Loose and scrape able

5355

SC 05355

11

Silt

Loose and scrape able

Treat

Evaluation of resources / needs Reut.

Reutilization

Resources

Needs

Difference

% Difference

0

Deposit

1,169,245

2,235,000

-1,065,755

48

1

Embankment

3,571,485

3,524,282

47,203

1

2

Upper part of earthworkssubformation 12

747,343

714,067

33,276

4

5

Upper part of earthworks subformation 2

9

Capping layer

917,244

0

917,244

100

10

Roadways

139,573

0

139,573

100

0

Volume by transport shop - Lalanne drawing

- Earth moving studies


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March 2007


- Earth movement – work


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March 2007


B – Earthworks technology B.1 – Clearance of land requirements B.1.1 – Area concerned The land requirements concern the surface area of ground relating to construction of the structure and its ancillaries. The area concerned includes final or temporary acquisition of land, its clearance, stump extraction, deforestation, movement of networks, demolition of structures, safeguarding of archaeological sites and stripping.

B.1.2 – Technical referential •

development of main highways (ARP) [5];

•

Ministry Circular No. 1 of 4 January 1968.

B.1.3 – Issues involved • clear definition and acquisition of the land requirements; • drawing up the inventory of the various requirements and constraints relating to networks and structures, and estimation of the required timelines to define the work (archaeology, gas, water, etc.); • crossing with existing infrastructures; • allotment of work to clear land requirements.

B.1.4 – Influential parameters • • • • •

the type of soil occupation (crops, meadows, woods, etc.); results of consultation (managers of networks, residents, groups, etc.); procedural uncertainties and timelines; archaeological and environmental assets; influence of weather conditions on stripping.


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March 2007


B.1.5 – Execution phasing Execution phasing DCE Design

Points to be examined Inventory of all overhead and underground networks, wells, marl pits, karsts, old explosive dumps and war galleries, enclosures, archaeological and geological sites (palaeontological and mineralogical), protected biological sites (fauna, flora, etc.).

Observations Recommendations Establishment of an extremely accurate plan of all networks, definition of their overhead or underground locations. Draw up a summary document as clearly as possible, to be given to contractors at the tendering [DCE] stage, and explain to the companies the order of clearance of the land requirements. Ensure consistency with PPSPS.

Definition of landmarks and traverse lines. C l l ti fl t d l ti Definition of destination of demolition products from stripping and d f t ti

Pay close attention to “risk” buildings (e.g. transformers, industrial buildings, b t f iliti )

List of required site roads and t di i Define the work to be carried out with administrators, and schedule them so that they are completed before the launch of earthworks. Site preparation

Planning of work to clear land requirements.

Preparation for execution

Establishing and examining procedures for execution. Design and precise layout and setting out of site access routes. Mark out deforestation areas, archaeological excavations, areas for brush cutting, areas of flora and fauna to be preserved and stripping zones, and mark out existing networks.

Execution

Organize excavations, particularly in the event of interference with other sites.

Setting out of land requirements and traverse lines. Preparation of accesses and entrances, construction of site enclosures and execution of site clearance work. Diversion of overhead power lines. Deforestation. Post-felling inspection.

B.1.6 – Monitoring to be carried out Conservation of pegging and traverse line.


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March 2007


B.2 – Site roads B.2.1 – Area concerned These are roads envisaged in the contract, reserved for site activity, for the following purposes: • access or link-up between certain structures or specific points; • reinforcement of existing routes.

B.2.2 – Technical referential •

New roads with little traffic – Design manual [2];

•

Use of expanded polystyrene in road construction [20];

•

Guide to design of roads with little traffic (CTGREF).

B.2.3 – Issues involved • • • • •

temporary, integrated or final nature; sizing; geometric characteristics; nature of the materials; site road maintenance.

B.2.4 - Influential parameters • • • • • • • •

relief; nature and intensity of traffic; period and duration of service; hydric environment; earth movement; site road in the land requirement and outside the land requirement; sizing of the land requirement; consultation and environment.

B.2.5 – Execution phasing B.2.6 – Monitoring to be carried out Not applicable Execution phasing DCE design


- setting and sizing of site road

Consideration of means of execution.

- property administration - sizing in accordance with purpose - allotment - environment - overcoming obstacles Site preparation

Execution

Site roads can be covered by a separate contract

- availability of land requirements - consideration of stresses


Observations Recommendations

Particularly certain networks (electric power lines, etc.).

- inventory - definition and examination of methods and means of execution - pegging - as per the methods and means approved - maintenance


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March 2007


- possible rehabilitation - possible assignation


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March 2007


B.3 – Weather conditions and earthworks B.3.1 – Area concerned For sound operations on earthworks sites in general, weather conditions have considerable consequences on the techniques to be implemented (reutilization of soils or treatment) in terms of work times and site economy. The area concerned includes geological and geotechnical surveys, identification of water-sensitive soils, collection of meteorological data, their use and monitoring.

B.3.2 – Technical reference documents • Weather conditions and earthworks - Recommendation [17]; • Construction of embankments/fills and capping layers (GTR Technical Guide to Embankments & Fills) [10].

B.3.3 - Issues involved The objectives pursued are: • optimization of earth movement and reutilization of soils; • evaluation of the importance and distribution of inclement weather for the timeline assigned to the site; • establishment of the precipitation thresholds which could entail site stoppage; • consideration in studies of climatic uncertainties and their consequences on the cost of work; The characteristics of the project have direct incidence on the variable sensitivity of the soils to meteorological phenomena (proportion of sensitive soils, topography, geometry and phasing of the project, period of execution). Water-sensitive soils could have repercussions on organization of the site, capacity, trafficability, slipperiness and possibilities of reutilization to ensure the structure’s stability.

B.3.4 – Influential parameters • climatic areas; • water-sensitive soils: nature, status, proportion of different soils; • period for execution of the construction work; • timelines: site duration, envisaged number of stoppage days; • water: effect of water on sensitive soils; • project characteristics: topography and geometry of the project (longitudinal profiles and cross sections); • hydrogeological conditions (water tables); • proportion of sensitive soils and their reutilization (sensitive = aptitude of soils to change status); • nature of the capping layer; • phasing constraints; • rain erosion (influence on work procedures and quality of structures); • storms creating erosion and destroying the structures built; • fog creating dangerous conditions and site stoppages; • rain, sun, wind and snow, which all affect water content (the wind can prevent hydraulic binder treatment); • frost (frequency and intensity) which accelerates the alteration of changeable materials and can create water concentrations in frost-susceptible soils.


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March 2007


B.3.5 – Execution phasing Execution phasing DCE design



Identification, location and quantification of water-sensitive soils.

On the basis of geological and geotechnical data.

Collation of meteorological data. Study of at least 2 earth movement solutions with favorable and unfavorable climatic conditions. From this, deduction of strategic choices to be imposed on earth t d t t i th t t

Over 30 years if possible. In relation to price, this procedure allows us to work out possible variations in costs and to adapt the tolerance margins of the estimate.

Writing up administrative documents Attach the information document setting (clauses on price variations and possible out all the meteorological information. prolongation of the schedule). Site preparation

Organizing the collection and use of meteorological data (staff, materials, contacts, quality assurance plan (PAQ).


Establishing and examining procedures for execution. Marking out areas of water-sensitive soils.

Deduction of stripping modes and the way in which materials are to be extracted.

Execution

Monitoring of procedures, collation of meteorological data, protective measures to be taken: - platform finishing; - temporary drainage; - development of outlet; - maintenance of site roads (to avoid water-sensitive soils).

Slopes, closures.

B.3.6 - Monitoring to be carried out Functioning of drainage.


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March 2007


B.4 - Topsoil B.4.1 - Area concerned The quality and administration of topsoil must be examined as of the project stage during the geotechnical bore procedure, by the project owner. If this is not possible, a preliminary topsoil study must be carried out prior to design of earthworks and landscaping for tendering [DCE]. On the basis of these studies, the topsoil movement plan and the conclusions in the study report will determine the quality of landscaping development in terms of geometry and of plantations.

B.4.2 – Technical referential • Section 2 of the general technical specifications (CCTG) for General Earthworks [49]; • Section 35 of the general technical specifications (CCTG) for Landscape Development [50]; • Execution of embankments/fills and capping layers (GTR Technical Guide to Embankments & Fills) [10]; • Technical guide to use of soils to construct green roadside ancillaries (Sétra) [14]; • Earthworks – Assistance in drawing up the particular technical specifications (CCTP) – Methodological Guide [19].

B.4.3 - Issues involved • estimation of stripping thickness and determination of needs; • storage of topsoil; • identification by specific studies of the three qualities of topsoil; • quantification and allocation of topsoil categories by types of rustic or complex development and by parts of structure; • topsoil handling conditions; • physical and physical-chemical corrections of topsoil; • topping and thickness of topsoil on slope gradients; • management of spaces and plantations.

B.4.4 - Influential parameters • needs in terms of topsoil by typology of spaces (link section, interchange, rest or service area, restoration of communication); • surfaces and nature of flat unprepared soil and on slope on link section; • agronomic analysis; • structural stability of earth; • settlement sensitivity; • moisture condition of earth and handling conditions; • physical-chemical analysis with contents of organic material, pH, carbon/nitrogen ratio, etc.; • chemical analysis (nitrogen, phosphorus, potassium, etc.); • phytotoxicity test, particularly for agricultural soils; • geometry of slopes, interchanges and restoration of communication; • topsoil movement plan; • special conditions for work, particularly the type of machinery to be used, in accordance with changes in climate; • the quality of earth extractions and depositing; • fertilizing fillers during execution; • management of landscape spaces (human and material resources, available credit, accessibility of spaces, safety, etc.).


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March 2007


B.4.5 - Execution phasing Observations Recommendations

Execution phasing


DCE design Earthworks

• evaluation of needs in relation to topsoil (TV) by space typologies; • qualitative and quantitative study of topsoils in place in terms of the 3 categories of earth; • quantity of ordinary topsoil for rustic development; • average quantity of topsoil for rest areas, interchanges, plantation ditch; • quantity of upper topsoil for roundabouts or urban areas; • movement plan for topsoil established during the project studies stage or in specific preliminary studies before drawing up the earthworks tender documents [DCE]; • earth storage and handling conditions; • with the manager, define implementation of the accesses required for maintenance of ancillaries, but also during the plantation stage.

• except in the case of lower slopes, topping is to be banned for gradients ≥ 1/1. With 3-D equipment, however, topsoil may be implemented; • topsoil may be used for low 3/2 slopes and for certain soil types. However, hydraulic spread replanting on unprepared soil is sufficient for 3/2 slopes; • toppings on slopes with gentler gradients vary from 5 cm to 15 cm, depending on the type of vegetation; • attach the topsoil movement plan with the earthworks DCE for information purposes; • add the specifications relating to handling conditions to the particular technical specifications (CCTP) for earthworks; • make arrangements for access every 1 or 2 km. Width will be at least 3m, and 4 m on curves. Maximum slope will be 50%.

Site preparation

• availability of land requirements and temporary and “final” deposit locations (pending the landscaping DCE); • reminder of the conditions for earth handling and ensuring its lasting quality (contractor’s proposal); • make arrangements for additional topsoil analyses within the context of the additional geotechnical studies by the contractor.

• in the prices specification, clearly define the conditions for maintaining the quality of earth and non-pollution of earth; • compulsory provisions to be envisaged on land which is inaccessible before the project owner for the road takes up possession.

Execution

• observance and monitoring of the procedures laid down in the topsoil movement plan and the conditions for handling; • temporary and final deposit in moist areas or areas with surface runoff; • post-felling inspection plan for stocks and deposits of topsoil by categories.

• implementation of the various categories of earth appropriate for each space typology; • supervision to ensure the earth is not contaminated; • supervision of slopes, and creation of ditches if required; • cover and grass over erodable soils and slopes as soon as possible; • sound definition of services in the prices specification.


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B.4.6 - Monitoring to be carried out For the landscaping DCE design stage, in order to select the best seeds and vegetation for each type of unprepared soil and topsoil implemented, a specific study after the earthworks stage or when it is ongoing must be carried out to characterize the soils in place after work, and to estimate permeability and root development potential in the soils.


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March 2007


B.5 - Cuts B.5.1 - Area concerned Extraction and removal of soils and/or rocky materials in accordance with a pre-defined project geometry, for optimum reutilization.

B.5.2 - Technical reference documents • Regulation NF P 11-300 [45]; • Creation of embankments/fills and capping layers – technical guide - (GTR Technical Guide to Embankments & Fills) [10]; • Treatment of soils containing lime and/or hydraulic binders - technical guide - (GTS Guide to Treatment of Soils) [13]; • Section 2 – General earthworks – General Technical Specifications (CCTG) [49]; • Guide to drafting the Particular Technical Specifications (CCTP) for earthworks [19]; • Use of expanded polystyrene in road construction [20]; • Road drainage – technical guide [21]; • Weather conditions and earthworks - Recommendation - [17].

B.5.3 - Issues involved • design of the stability of slopes; • observance of geometry (slopes), mainly for rocky materials; • temporary and final drainage arrangements; • conditions for phasing and method of operation; • drainage phasing; • sizes of blocks of material; • sorting of mix and homogenization; • design of the upper parts of earthworks (nature, drainage, etc.); • observance of environmental commitments; • appraisal and possible study of the risk of swelling in bottom section of cuts (decompression and effects of water);

B.5.4 - Influential parameters • • • • • • •

nature and condition of materials; land requirements; water tables and water ingresses; weather conditions; environmental problems; longitudinal section (effects on drainage); earth movement.


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March 2007


B.5.5 - Execution phasing for cuts Execution phasing DCE design

Points to be examined • definition of stresses for earth movement; • verification of consistency between earth movements and phasing constraints; • definition of final drainage and sewerage, and possibly the prior or temporary drainage facility.

Observations Recommendations • on its quality assurance plan’s organizational chart (SOPAQ), the contractor must set out its proposal for earth moving in due observance of the stresses and methodologies for operation of cut works.

• constraints relating to homogenization and preparation of the materials i d • strategy for design and compensation of site roads; • geometric characteristics and nature of specific devices and systems to ensure stability of slopes; • classification of the upper parts of earthworks and subformation, and possible improvement of subformation (see singular points); • environmental constraints (thresholds in terms of vibration, noise, dust); • maximum objective for sizes of blocks of materials; • validation sections (mining, water ingresses); • strategy for compensation, particularly for transport of 1st and 2nd category materials. Site preparation


• additional investigation; • validation and updating of studies; • clearance or disengagement of the land requirement by the project owner. • verification of materials and validation • Calibration and verification. of procedures for execution put forward for the quality assurance plan (PAQ). • for rocky cuts, definition of the contents of the validation test.


– 73 –

• Validation test to be carried out or adapted in accordance with the size of the site. The objective of this test is to provide indications to the construction manager on the contractor’s ability to reach the level of quality required.

March 2007


Execution phasing Execution



• nature and condition of materials before and after production or treatment stages; • adaptation of earth movement in accordance with the materials actually found and with weather conditions; • temporary drainage / sewerage; • geometric conformity of the work carried out; • verification of conformity and functioning of final drainage and sewerage systems; • verification of conformity of classification of the upper parts of earthworks-subformation; • possible adaptation of reinforcements to stability of slopes.

B.5.6 - Monitoring to be carried out Monitoring of stability and content of slopes (piezometric measurements, possible clinometrical measurements).


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March 2007


B.6 - Embankments & Fills B.6.1 - Area concerned Construction of general embankments/fills on terrain which is generally flat, using natural materials, height low to average ≤ 15m, on a non-compressible support, including the upper part of the earthworks. If the soil is compressible, see file “Embankment on compressible soil” in this chapter, and in the technical guide “Study and construction of embankments/fills on compressible soils” [8].

B.6.2 - Technical referential • • • • • • • •

Regulation NF P 11-300 [45]; General Technical Specifications (CCTG), Section 2 General earthworks [49]; Guide to drafting the Particular Technical Specifications (CCTP) for earthworks [19]; Creation of embankments/fills and capping layers (GTR Technical Guide to Embankments & Fills) [10]; Treatment of soils containing lime and/or hydraulic binders (GTS Guide to Treatment of Soils) [13]; Use of expanded polystyrene in road construction [20]; Road drainage – technical guide [21]; Weather conditions and earthworks - Recommendation - [17].

B.6.3 - Issues involved • designing a structure with materials and implementation in sufficient densification to ensure that after construction there is no long term risk of significant deformation (swelling, settling, breaks in slope, etc.); • designing the upper part of the earthworks with deformability characteristics compatible with the short and long term objectives; • designing a slope gradient (in the case of land requirement issues); • observance of environmental commitments.

B.6.4 - Influential parameters • • • • • • •

land requirement (slope gradient, width of construction limits, wall, etc.); weather conditions (reutilization of materials, earth movement, trafficability, etc.); nature and condition of the bearing soil (height of the embankment, etc.); nature and condition of the materials (earth movement); height of the embankment (>10 m, 5 - 10 m, <5 m, built low on moist support); hydrology and hydrogeology of the site; environment (topsoil, grass sowing).


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March 2007


B.6.5 - Execution phasing for the embankment Execution phasing Preparation of the support

Improvement of the support

Execution of the main body of the embankment


Points to be examined Stripping

Necessary if height < 3 m embankment.

Stump extraction

Due observance of the rules of the art, otherwise there is a risk of settlement for low to medium heights (rotting, t )

Compaction of support (if the support is not deformable)

Necessary if the support is disorganized (stripping, stump extraction).

Support quality problem (in the sense of Treatment in situ, drainage and/or deformability) if height < 1 – 1.5 m substitution. H i ht > 1 5

Thi k l

d i

ti

The base of the embankment could be invaded by water ingresses

Drainage materials at the base of the embankment, foot drainage in association with treatment for the base of the embankment.

Earth movement and weather conditions (excluding heterogeneous embankment → see singular points). Nature and condition of the materials.

Application of GTR Technical Guide to Embankments & Fills and GTS Guide t T t t f S il

Nature of the materials,

Verification of adaptation to the di t f th l

Compaction of edges of embankment, t i l

Definition of the method and quantities i d

Temporary and final drainage/sewerage. Ridges + drainage channels Water management during the construction works stage. Embankment slope

Execution of upper parts of earthworks


Protection

Topsoil and/or grass sowing.

Water-sensitive coherent materials and soils or rock materials from altered or shaley but fragmentable rock

• if height ≤ 5 m → p ≤ 2/3 • if 5 ≤ height ≤ 10 m → p ≤ ½ • if height > 10 m, no general rule – the slope must be defined by a stability study.

Non-water sensitive granular materials of alluvial origin or rocky materials from soft non-shaley rock.

• if height ≤ 5 m → p ≤ 1/1 • if 5 ≤ height ≤ 10 m → p ≤ 2/3 • if height > 10 m, no general rule – the slope must be defined by a stability study.

Materials from hard unaltered rock.

• •if height ≤ 5 m → p ≤ 1/1 • if 5 ≤ h ≤ 10 m → p ≤ 1/1 • if height > 10 m → p ≤ 2/3 with berm.

Adaptation of materials to the bearing capacity objective assigned to the upper parts of the earthworks.

Check whether the site materials reserved in the earth movement could suit natural status or after treatment and over which thickness. If this is not the case, a less ambitious objective must be envisaged or a filler material must be sought out.

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March 2007


Others


• Earth mound barriers. • Deposits added to the embankment.

– 77 –

When these are added to the embankment, drainage must be arranged for the interface and collection of surface water.

March 2007


B.7 – External fillers or borrowings B.7.1 - Area concerned Cuts or fillers outside the land requirement of the main structure to palliate a quantitative or qualitative shortage of natural or industrial materials (class F, GTR Technical Guide to Embankments & Fills).

B.7.2 - Technical referential • • • • • • • •

Regulation NF P 11-300 [45]; Creation of embankments/fills and capping layers (GTR Technical Guide to Embankments & Fills) [10]; Treatment of soils containing lime and/or hydraulic binders (GTS Guide to Treatment of Soils) [13]; Section 2 of General Technical Specifications Guide to drafting the Particular Technical Specifications (CCTP) for earthworks [19]; District quarry diagram Impact studies Mining Code [51].

B.7.3 - Issues involved • • • •

Definition of qualitative and quantitative needs Transport means and routes Will natural deposits provide the required quantities of materials? Obtaining the required permits (issues relating to timelines and authorizations)

B.7.4 - Influential parameters • • • • • • • • • • • • • • • • •

nature, quality and quantity of materials; accesses; homogeneity of the natural deposit; complexity of the natural deposit; borrowing distance to the areas to be filled in (conditioning the type of transport device); possibility of using classified facilities (extraction, washing, screening, storage); district quarry diagram; coordination of earth movements; environmental constraints (dust, etc.); mining; vibrations, water; redevelopment constraints on borrowing; timelines (in the sense that studies have to be launched well in advance – technical/administrative timelines); morphology of the deposit (floodable sections, rain, etc.); property administration (temporary occupation, authorization by owner of site, negotiation of mineral rights); complexity of the deposit; borrowing distance to the areas for implementation (conditioning the type of transport device).


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March 2007


B.7.5 - Execution phasing for borrowing Execution phasing



DCE design

• quality objectives; • principles for operation of borrowing; • inventory of studies to be implemented during the “site preparation” stage; • specifications in the application for permission to open a quarry; • specifications and design, if required, for accesses; • opinion of services; • definition of the operating constraints; • strategies for compensation (weighbridges, etc.); • specifications for redevelopment with the timeline.

Ask the contractor to provide a method for the operation of borrowing on its quality assurance plan’s organizational chart (SOPAQ).

Site preparation (2 - 3 months at start of site, or 2 – 3 months before execution)

• additional investigation; • validation and updating of studies; • observation of the condition of transport routes.

Attention must be drawn to adaptation between the objectives and the means of investigation (e.g.: depth of investigation); Set investigation timelines in accordance with the size of the site.


• preparation or improvement of accesses if required; • validation of the process of production of materials in such a way that it will be able to meet the objectives.

Execution of extraction and production

• nature and condition of materials before and after production or treatment stages; • ensure permanent observance of obligations in the order issued by the Préfet; • final verification of the condition of transport routes.

B.7.6 - Monitoring to be carried out Ensure that all environmental commitments and commitments with regard to the owner of the site have been observed.


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March 2007


B.8 – Final deposits and earth mound barriers B.8.1 - Area concerned • use of natural cut materials, surplus materials and/or poor quality materials with geometric characteristics imposed on: - landscaping development, - development for noise protection, - development of agricultural land. • site waste (see the topic concerned); • in certain cases filler materials may be used for certain earth mound barriers.

B.8.2 - Technical referential • • • • •

Regulation NF P 11-300 [45]; Use of expanded polystyrene in road construction [20]; General Technical Specifications (CCTG), section 2 – General earthworks [49]; General Technical Specifications (CCTG), section 35 – Landscaping development [50]; Guide to drafting the Particular Technical Specifications (CCTP) for earthworks [19].

B.8.3 - Issues involved • in accordance with earth movement, investigation of areas which could take in surplus and/or poor quality materials, defining geometry and volumes to guarantee stability and site integration without disturbing the flows; • in the case of earth mound barriers or imposed landscaping mounds, mostly built using materials of lower quality than those used for the main structure, ensure that the stability of the embankment built is compatible with the geometric characteristics imposed.

B.8.4 - Influential parameters • • • • • • • • • • •

availability of land and access to it; geometry; topography; environmental constraints (Water Act, noise protection); flows; landscaping development and nature of the plantations; earth movement; hydrogeology of the deposit sites; nature, quality and quantity of materials; final destination of the deposit (redevelopment constraints); regulations concerning waste dumps.


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March 2007


B.8.5 - Execution phasing of a deposit and an earth mound barrier Execution phasing



DCE design

Estimate the volumes and nature of non- Define precisely the deposits and earth reusable materials and surpluses, and mound barriers with imposed geometry, define and locate their destination. particularly in cases where the nature of the materials imposes specific constraints (e.g. soft soil for evacuation: • plan with location of deposits to allow the contractor to provide its price; • specify the volumes of deposits to be covered by the contractor; • ask the contractor to specify the method it intends to use in order to implement deposits on the quality assurance plan’s organizational chart (SOPAQ); • the SOPAQ chart must contain the specifications for redevelopment of deposits.

Site preparation

Actual availability of land; Report on condition of transport routes.


Preparation or improvement of accesses if required. Preparation of the possible stripping and drainage/sewerage area. Validation of the method of execution proposed in the quality assurance plan.

Execution

Verification of proper application of the destinations set out in the DCE. Verification of the nature and proper destination of the materials. Observance of initial commitments for redevelopment, and final report on condition of transport routes.


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March 2007


B.9 – Embankments & fills on compressible soil B.9.1 - Area concerned Construction of embankments/fills on soils with a considerably deformability rating, low permeability and low resistance. The following are often found in these saturated or quasi-saturated soils, known as “compressible soils” or “soft soils”: • peat; • silt; • soft clays; • clayey or loose silt; • loose sand; • loess and some recent poorly compacted embankments/fills.

B.9.2 - Technical referential •

Studies and construction of embankments/fills on compressible soils – technical guide [8].

B.9.3 - Issues involved • feasibility of the embankment in accordance with the characteristics of the soil and the height of the embankment; • the overall stability of the embankment and surrounding structures; • deformations caused by settlement of the compressible soil; • parasite strains caused by surrounding structures (building, bridges, SNCF railway lines, pylons); • limitation of long term differential settlement; • disturbances in surface water flows (embankment on a low level in a floodable valley), but also in subsurface water flows; • breakage of bearing soil during work or long term; • embankment construction time; • is an embankment the only solution? (bridge, viaduct).

B.9.4 - Influential parameters • geotechnical investigation during the choice of passage area or areas in overview / background summary studies; • progressive investigation of the site and the soils from preliminary studies to the project studies stage; • depth and thickness of the compressible soil; • the height of the embankment; • the width of the platform with respect to the final implementation width (wider land requirement); • embankment construction technique; • amplitude of deformations tolerated after implementation; • the project’s environmental constraints; • the project’s geometric constraints (ability to modify the longitudinal section after implementation); • independence of road drainage with respect to deformations and settlements; • order of work; • time between the beginning of geotechnical investigation, actual work (construction in stages) and stabilization of the embankment (absence of any soil deformation?); • availability of materials for temporary overloads or for stabilization bench terraces; • the technical-economic study for solutions (cost of studies + cost of construction + cost of maintenance).

B.9.5 - Solutions advocated The solutions advocated by the guide “Study and construction of embankments/fills on compressible soils” [8] Collection « Les outils” – Sétra

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are set out in annexes 1 - 15 (page 38 of the guide), namely: • construction in stages; • lateral bench terraces; • temporary overload; • lightened embankments/fills; • geosynthetic reinforcement; • substitution of poor soil; • vertical drains; • atmospheric consolidation; • ballast columns; • crushed ballast studs; • mechanical injection; • jet-fashioned soil-cement mortar columns; • soil columns treated with lime or cement; • embankments/fills on rigid inclusions; • electro-osmosis.


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B.9.6 - Execution phasing Points to be examined


DCE design Earthworks

• the construction manager’s schedule of project studies and additional studies to the contractor’s account; • details of the methods of execution; • summary of settlement effects; • precise description of the technical solution; • definition of the means of execution (monitoring equipment, supervision of work, etc.); • the ad hoc sewerage facility; • quality and scope of the contractor technician in charge of work (a component of the quality assurance plan’s organizational chart [SOPAQ]); • compatibility of timelines with general planning of the operation; • envisaged duration of the various stages of earthworks and any preloading; • quality of the geotechnical engineering firm approved by the contractor; • halt points and possible critical points required for external checking (article 5.5 page 73 of the November 2000 technical guide).

• the first three points opposite arise from evaluation of sizing studies, and must be integrated in the quality master plan (ESDQ) drawn up after the DCE and before the call for tender; • attach the full geotechnical reports with all the results, and state justification for the structures; • full precision with regard to all the technical requirements of the Particular Technical Specifications (CCTP), and verification that the prices specification fits articles in the CCTP with these requirements and the required quality; • the sewerage facility must be able to function despite any deformations, and be accessible for the purposes of modification and adaptation; • beyond the classic requirements demanded in the quality assurance plan’s organizational chart (SOPAQ), the chart must consist mainly of the points opposite. (there must be a reminder of these items in the tendering regulations/SOPAQ, and especially in the judgment criteria if the construction manager requires this).

Site preparation

• inventory, particularly of existing structures (buildings, networks, etc.); • the topographical reference system: • the condition of the soil before loading; • instrumentation for the site / monitoring; • direct restitution by the construction manager of the content of studies for the contractor; • precision of procedures for execution and halt points through the quality assurance plan; • the means implemented, and timelines; • quality and scope of the person responsible for the site in the contractor’s company.

•this “zero” inventory will help us judge the extent of any subsequent damages caused by the site; • this topographical reference must be located outside the area sensitive to deformations, or constitute a special stable structure (pile anchored in the substratum, laying of settlement gauges); • reminder of interruption stages for measurements and switchgear; • the quality report (SDQ) drawn up by the construction manager at the end of the preparation period constitutes an essential factor in relation to approval of work quality.

Execution phasing


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Execution phasing Execution



• proper application of the quality procedure in reference to the quality report [SDQ] and the quality assurance plan; • a uniform gradient for the b k ti l

• the maximum discrepancy authorized i i l l

• validation of studies and calculations of sizing with respect to reports on t

• these volumes are calculated from checks on measurement of settlements;

• the volumes of materials implemented; • technical adaptation in view of measurable evolutions tending to make the structure unstable; di i ti f i t titi l • observation of timelines for consolidation;

• the attention of the contractor must be fully drawn to these timeline issues they must be quantified if possible, and prices must take account of reasonable i d f ibl

• continuity of the drainage base;

• the effectiveness of this layer must be guaranteed, as must the flow of water upstream, avoiding construction of t f hi ld

• proper functioning of the temporary drainage/sewerage systems; • implementation of side ditches and their slope.

• implementation too close to the foot of the embankment or a bench terrace can harm the stability of the structure; Likewise, too faint a slope may be modified by settlements and create a water trap.

B.9.7 - Monitoring to be carried out Monitoring basically concerns settlements and measurement of interstitial pressure levels, and so the settlement gauges and other instrumentation on site must be kept in a good state of repair. Likewise the leveling indicators and reference posts will be kept in good condition. In due consideration of residual settlement, monitoring of the proper functioning of the road platform’s drainage and sewerage system will be implemented. The attention of the manager of the road network will be drawn to probable activity to recharge the flexible pavement (no rigid structure and capping layer treated with hydraulic binders) after deformations inherent to residual settlement or in order to start work on larger projects. Materials making up the embankments/fills and the upper parts of earthworks may, however, be improved by lime treatment if required.


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B.10 – Blasting earthworks B.10.1 - Area concerned Blasting earthworks are works carried out in the open air with rocky materials, where materials can no longer be extracted by scraping work. This technique is used: • to extract cut materials for subsequent use in riprap embankments or, after crushing and screening, on the capping layer or the roadway itself; • to ensure proper geometry and landscaping for the slopes of rocky cuts.

B.10.2 - Technical referential • Blasting earthworks in roadwork sites [11]; • Guide to drafting the Particular Technical Specifications (CCTP) for earthworks [19].

B.10.3 - Issues involved Well before the DCE stage, earthworks in blasting rock require specific additional classic investigation studies, particularly in relation to: • configuration of rocky formations encountered on the project alignment; • tectonics affecting the rock mass (faults, discontinuities, folds, fractures); • the physical and mechanical characteristics of rocks to be quarried (petrographic identification, strength, abrasiveness, alteration); • hydrogeology (hydraulic load, permeability prior to work). Following overview / background summary [APS] and project studies investigations, all these factors require essential in-depth studies without which it is impossible to arrange a realistic study of the method of extraction or quarrying, properly evaluate the costs of earthworks, draw up a good DCE, protect the environment and the durability of existing structures located at critical distances, depending on the type of structure.

B.10.4 - Influential parameters • a basic geotechnical study considering a rocky medium; • a specific additional study in relation to the structure and nature of the rocky mass to be extracted; • the presence of water in the medium; • mode of extraction (quarrying in large or small masses, blasting holes for purging, construction of trenches or excavations of structures); • reutilization on embankments/fills, capping layer, road or riprap (sizes of blocks of materials); • geometry of rocky slopes (make profiles which are too technical natural – land requirement); • stability of remaining block (no “rear effect”); • sensitivity of structures located in critical areas; • initial inventory of built structures; • thresholds in relation to particular speeds and frequencies; • planned and actual blasting patterns; • test blasting; • problem of projections (work in urban areas in particular); • quality and competence of the contractor and the mining team.


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B.10.5 - Execution phasing Execution phasing DCE design

Points to be examined • the full geotechnical report

Observations Recommendations • this report must be attached for information purposes, to allow the contractor to choose the blasting extraction method freely, in accordance with the nature of the materials

• classification of the materials to be cleared in one or more zones in accordance with extraction difficulty


• granularity of the materials to be extracted in accordance with their reutilization

• the sizes of blocks of materials must be adapted to prevent the deposit of large blocks (waste). Thus there must be no compensation for block reduction (this must be included in the price of blasting cuts)

• environmental constraints (vibrations, noise, projections) •inventory of structures and establishment of thresholds

• provision of information to residents and mayors • set out in the Particular Technical Specifications (CCTP) and the BP prices specification and all ongoing cases a specific maximum speed of around 5 mm/s over a frequency range of 2 – 6 Hz • arrangements for vibration checking of structures on each blast, and post-blast checks to ensure that the thresholds have not been breached • the Particular Technical Specifications (CCTP) and the BP prices specification must envisage the use of anti-projection facilities (grilles, bales of straw, geotextiles or metal shields (in urban areas).

• landscape integration of rocky slopes

• consideration of safety during the execution stage, but also during the operational stage. Land requirements must be adapted to monitoring, maintenance and the needs of integration. Incidence of the “rear ff t” t 10 f bl t

• competence of the contractor or the subcontractor

• the rules for tendering must require that the contractor or the subcontractor (fully approved) set out their experience in the quality assurance plan’s organizational chart (SOPAQ). The subcontracting contract must be forthcoming, and also the references of the mining team, mining methods and measures taken to protect local residents.

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Execution phasing Site preparation

Execution



• the quality assurance plan • envisaged blasting pattern

This must include the following: • the geometric characteristics for boring; • nature, quantities and distribution of explosives in each hole ; • nature of the devices; • starting sequence; • exhaustive list of constraints.

• initial condition of the structures

• the contractor must draw up a joint report with a witness, an official or an expert, and an inventory of all the structures located in critical zones (inventory of existing fissures, separate claddings, settlements, etc.).

• the Special Plan for Protection of Health and Safety (PPSPS)

• proper definition of conditions in relation to mining operations

• observance of regulations with respect to authorization for use of explosives and conditioning for use of explosives

• the construction manager must obtain a copy of the official documents, and add in the employees covered by the Préfet’s authorizations

• test blasting (validation) for correct definition of the vibration characteristics

• verification of the exactness of the conditions of the planned blasting pattern, showing whether the thresholds have or have not been obtained; • care must be taken with surface waves - these can be harmful, even at a considerable distance from blasting (atypical vibrations).

• the actual blasting pattern

• the construction manager will only authorize blasting if the detailed blasting pattern has included all the difi ti dh b b itt d

• structural damage to buildings or other • proper identification of the origin of structures the phenomena, justifying complaints (vibrations transmitted through the soil or the atmosphere); • carefully study all the vibration checks, and redefine a blasting pattern if • quality of the rocky landscape slope

• check absence of parasite fissure t bilit ft bl ti

• granularity of the materials extracted

• check that Dmax is compatible with tili ti

• the document for subsequent work on structures (DIUO) and maintenance of the rocky slope

B.10.6 - Monitoring to be carried out Monitoring of the stability of slopes.


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B.11 – Waste and by-products B.11.1 - Area concerned This concerns the planning of site waste management in accordance with the law of 13 July 1992 governing waste disposal, recovery of materials and classified facilities for protection of the environment. Waste from earthworks is normally inert homogenous waste, unless it is from polluted soil or specific products such as pipes, posts, metals, bitumen products, tar, vegetation, etc. It also concerns the use of industrial waste and by-products such as the use of blast furnace slag, black bat, quarry and mining waste, incinerator ash from domestic refuse (MIOM), demolition material, plastics, used tires, steel slag, foundry sand, lime slurry, sludge from purification units, etc.

B.11.2 - Technical referential Main legislative and regulatory references Law No. 75-633 of 15 July 1975 on disposal of waste and recovery of materials. Law No. 76-663 of 19 July 1976 on classified facilities for protection of the environment. Law No. 92-646 of 13 July 1992 completing and modifying these two laws. Law No. 95-101 of 2 February 1995 (the Barnier Law) on increased protection for the environment. European Directive 75/442/CEE modified by directives 91/156/CEE and 96/350/CE. Environmental Code, book V, title IV on disposal of waste and recovery of materials. Environmental Code, book V, title I on classified facilities for protection of the environment and Ministry of infrastructure, transport and housing, 15 February 2000, in relation to planning for waste from building sites and public works. Circular from the Ministry for development of territory and the environment on the implementation of district plans for disposal of household and assimilated waste, 28 April 1998. Circular from the Ministry for development of territory and the environment and the Ministry of infrastructure, transport and housing on management of waste from the state highway network, 18 June 2001. Decree No. 94-609 of 13 July 1994 on non-household packaging waste. European Directive 1999/31/CE, council meeting of 26 April 1999, on waste discharging. Decree No. 97-517 of 15 May 1997 on the classification of hazardous waste. Decision by the Commission on 16 January 2001 on the European waste list. CCTG General Technical Specification sections No. 2, No. 25, No. 27 and No. 35.

Methodological references (guides and recommendations, monographs, study reports) •

Management of waste from road construction and operation [15];

•

Repeated heat treatment of bituminous materials [16];

•

Guide to building site waste. Coll.: Knowledge for action [59];

•

Site and building waste. Guide to professional building usage [29];

• TRIVALOR, PODDEVIN, L. (1998). Environmental Research and Development Program. Challenges in relation to waste management by motorway concession companies. ASFA; •

Site surpluses and by-products, proposals and solutions (FNTP) [63];

• Regional guides to reutilization of waste and non-conventional materials (Ile-de-France, Normandie, Nord, Pas-de-Calais, etc.).


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B.11.3 - Issues involved Waste recycling and upgrading have been applicable since 1 July 2002, and only end waste is accepted at storage facilities as per the law of 13 July 1992. Waste upgrading ensures savings in natural resources by limiting their extraction, and thus related environmental issues (upgrading of metal slag waste in the Nord district, coal as hand incinerator ash from domestic refuse). For waste to be upgraded, a genuine construction product must be created with precise characteristics and obvious interest for use.

The obligations of the regulations are as follows: • as of 1 July 2002, compulsory upgrading of waste with the exception of final waste and access to technical landfill centers (CET) for these final waste products only; • responsibility of the project owner, producers and handlers of waste for implementation of an ecologically satisfactory solution to dispose of waste; • limitation of waste in terms of transportation and volume. Activities forbidden by regulations: • burning waste in the open air; • abandoning or burying waste in areas not controlled by the authorities; ( 1) • placing non-inert waste in class 3 landfill centers ; • leaving special waste on site or placing it in skips not intended for this purpose. Correctional sanctions for infringements of this law range from 305 Ä to 76225 Ä in fines and/or prison sentences of between 2 months and 2 years.

B.11.4 - Influential parameters The influential parameters are mainly set by laws and regulations. Waste is the term used for any residual material from a process of production, transformation or utilization, and also any substance, material, product or, more generally, any item which has been abandoned or whose producer intends to abandon it. The following distinctions are made: 1. Inert waste According to the ADEME environmental and energy agency, inert waste is waste which will not undergo physical/chemical change over time. 2. End waste This is waste which cannot be processing in current technical and economic conditions, particularly by extraction of the upgradeable component, or by reducing its pollutant or hazardous nature. With respect to roads, classification of waste allows us to determine its destination in accordance with its potential environmental nuisance or pollution. The negative effects of waste dumping must therefore be eliminated or reduced to prevent: • pollution of surface water and subsurface water; • greenhouse effect; • chemical and biological hazards in relation to animal and human health for the entire duration of the waste dump.

1

End waste is to be stored in accordance with its nature at technical landfill centers (CET): - class 1 for special industrial waste (DIS) - class 2 for household or similar waste (DMA) - class 3 for inert general industrial waste (DIB)


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B.11.5 - Execution phasing There must be full knowledge of by-products and waste prior to use in earthworks. The technical guides provide general descriptions of waste. Detailed studies at labs and experimental sites may be carried out to define the requirements for each type of use envisaged. These requirements relate to mechanical characteristics (mechanical performances, durability, etc.) in connection with possible pollution and also to the conditions of use.


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Disposal of waste (upgrading first, and then storage) must be taken into consideration explicitly in contracts. The contracts must encourage each agent to work towards upgrading or the most economic solutions overall, in due observance of legislation and regulations, for disposal of the waste they produce. For earthwork companies, excess materials may be considered as waste, or inert waste. However, where the contract stipulates reutilization of all materials on the site land requirement, no waste exists. On the other hand, excess material taken off the site land requirement may be considered as waste. The notion of waste emerges as soon as the contractor intends to dispose of it. Execution phasing DCE design

Site preparation




Studies of earth movements.

• maintaining a balance between cuts and embankments/fills; • defining a schedule for implementation of selective sorting, upgrading objectives, technical, human and financial means.

Waste upgrading potential.

• proximity of upgrading centers, sorting centers, recycling units, storage centers, incineration centers in accordance with district plans for waste disposal; • conditions for waste acceptance at these centers (sorted waste, volumes of waste, etc.).

Waste disposal procedures.

Study of compatibility of the strategy chosen with district plans for waste di l

Definition and choice of an appropriate sorting strategy.

• identification of waste (nature, volume); • procedures for disposal and estimation of costs; • preferential routing plans. Environmental stipulations including waste management and definition of the financial means provided will be added to the technical specifications. These stipulations will allow the contractor to draw up the organizational chart for waste disposal management (SOGED) for inclusion in the tender.

Appointment of a person in charge of all waste procedures.

Site workers must be made aware of environmental concerns. The issues of waste and/or reutilization (sorting, recycling, traceability and human and material means) must be developed through the environmental protection plan (PAE).

Implementation of measures to prevent waste production.

The entity creating waste or by-products used in earthworks must use a technical listing to set out the characteristics of his product, and this forms part of the contract. He must also use a suitable quality procedure to ensure conformity of delivery of this technical document vis-à-vis the construction manager.

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Execution phasing



Site preparation

Geotechnical, environmental and economic aspects.

In due consideration of the considerable variability of waste and by-products, only a quality procedure including all stages of the creation of such products can produce quality assurance. This procedure must form part of the quality assurance plan (PAE).


The use of waste and by-products in construction.

Validation sections and conformity testing must be drawn up if these are required.

Execution

Observance of stipulations in the DCE.

The supplier is responsible for the conformity of waste or by-products. The construction manager must ensure conformity. On site, checks by the construction manager must include observance of quality assurance. For certain types of waste, a direct logistics flow will be required with no intermediate storage (e.g.: incinerator hf d ti f (MIOM)

Recycling of materials.

Recycling of natural minerals, demolition materials (concrete, bituminous concrete, etc.) at fixed or mobile recycling units will have economic consequences on t t ti dd i ti Composting or recovery of energy from ti i d i t Checks must be carried out prior to reutilization of organic matter. Verification of geotechnical h t i ti Excess materials from cuts (earth and minerals) will be used in situ and on the site land requirements for qualitative development work (landscaping models, treatment of surplus land).

B.11.6 - Monitoring to be carried out For the purposes of feedback on the action taken, the following are necessary: • check on waste management by implementation of traceability facilities; • implementation of performance indicators (quantities collected, sorted, refuse recorded at the sorting center, economic evaluation) to monitor the schedule and make corrections geared towards improvement.


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B.12 – Sewerage and drainage B.12.1 - Area concerned 1) Above-ground sewerage system • on the platform; • at the foot of the slope or at the top of the cut. 2) Underground sewerage system • drainage trench or screen; • drainage layer. 3) Internal drainage • design of the drainage system, earthworks for the slopes, upper parts of the earthworks and the capping layer; • during the construction work stage.

B.12.2 - Technical referential • • • • • • •

Environmental Code; 1992 Water Act and decrees applicable [52]; Drain regulations; Geotextile regulations; Use of expanded polystyrene in road construction [20]; Road sewerage (GTAR) – Technical Guide [24]; Road drainage - Technical Guide [21].

B.12.3 - Issues involved Water and earthworks are never a good combination, and are often a synonym of more or less long term structural damage. The main problem is the design and sizing of structures in order to: • ensure the long-term intrinsic characteristics of sections of the structures: platform, slopes; • maintain or channel water flow through the structure; in order to maintain customary quality in the long term. Water has two origins: • meteorological: water falls on earthworks and flows over platforms and slopes to the foot of slopes or the top of cuts. “Longitudinal” sewerage systems collect the water and take it to an outlet, but these systems do not completely eliminate the risk of infiltration which can cause problems in the short and long term. It may be an idea, therefore, to build a continuous vertical screen in certain areas (river bank drainage). • water table, free or captive water: the objective of the structures is to intercept and reduce any risk of the water table rising. These stipulations are all the more necessary for structures next to natural ground: cuts, embankments at grade level, sections between cuts and embankments/fills. Implementation of a continuous vertical drainage screen under the top section of the earthworks is particularly useful in this case. In the case of slopes, the presence of water may be the cause of modifications to the intrinsic characteristics of soils, and may cause instability problems. In this case, the structures will have two objectives: to desensitize materials to the influence of water, and capture and evacuate the water (drainage trenches, weight shield, etc.). • • • • •

execution of earthworks imposes observance of water management rules in order to: ensure site trafficability; improve the moisture condition of the materials to be reused; treat isolated water ingresses (graduation of permeability between layers); maintain water flows across the site.

Temporary structures will be required for this during the execution stage.


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All these facilities may be located in interfaces with miscellaneous equipment: • the drainage system with water slides, structure piles, gantry feet, civil engineering on the Emergency Calls Network; • crossing of the Emergency Calls Network. Moreover, the civil engineering works for the Emergency Calls Network or the construction of platform sewerage and drainage works (drainage channel, etc.) must not under any circumstances constitute an obstacle to water flows or act as a “parallel drainage system”. Certain specific facilities may be required, such as drainage trenches towards the slope, or transversal drains. In all cases, care must be taken to ensure this does not constitute a screen to water flow by transversal installation of a less permeable material.

B.12.4 - Influential parameters • relief; • geotechnical features, nature, condition and thickness of geotechnical layers; • hydrogeology / piezometric characteristics; • meteorological conditions; • execution method and procedure; • sizing and hydraulic capacity of the structures; • constraints in terms of maintenance and operation; • performance of platforms; • erodability of soils; • characteristics of drainage materials; • thickness of the drainage layer; • flow to be removed; • collectors and outlets; • characteristics of outlets from the quantitative viewpoint (evacuation flow) and from the qualitative viewpoint (sensitivity / vulnerability).

Drainage system during the construction stage


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B.12.5 - Execution phasing Execution phasing DCE design



Identification, location and quantification: - water tables; - slope instability problems.

On the basis of geotechnical and hydrogeological studies.

For each type of earthwork structure (cut, embankment, upper parts of earthworks, etc.).

See the appropriate chapter.

Technical specifications in relation to supplies (drainage material, geotextiles, d i ) Weather conditions

See the appropriate chapter.

Prefectoral order for authorization in relation to water policing.

Draw up a contract for this.

Site preparation

• organization of collection of meteorological data; • nature and origin of materials (drainage material, geotextiles, drains).


• Validation of materials and of procedures for execution; • Verification of technical interfaces.

Execution

Protective measures and systems to be provided: - platform adjustments; - temporary drainage; - temporary facilities (ridges, etc.); - outlet facilities. Definition of temporary drainage. Verification of conformity and functioning of temporary drainage. Possible adaptation of the reinforcements for stability of the slopes. Permanent observance of the Prefectoral Administration and handling of exterior order for authorization in relation to waste (quantitative and qualitative). water policing.

B.12.6 - Monitoring to be carried out • ensure that all environmental commitments are met; • ensure administration of waste downstream towards third parties to prevent claims (Rural Code); • ensure proper functioning and cleaning of the network, also during the operational stage.


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B.13 - Capping layer B.13.1 - Area concerned Execution of the capping layer, with the characteristics required for the level of road support platform approved, with site materials, borrowings or exterior fillers used as-is or adapted for use.

B.13.2 - Technical referential • • • • • • • • • • •

Regulation NF P 11-300 [45]; General Technical Specifications (CCTG), section 2 [49]; Guide to drafting the Particular Technical Specifications (CCTP) for earthworks [19]; Creation of embankments/fills and capping layers (GTR Technical Guide to Embankments & Fills) [10]; Treatment of soils containing lime and/or hydraulic binders (GTS Guide to Treatment of Soils) [13]; Design and sizing of road structures [7]; Catalog of type structures for new roadways [1]; Use of expanded polystyrene in road construction [20]; Road drainage – Technical Guide [21]; Weather conditions and earthworks - Recommendation [17]; Regulations NF P 94-102-1, NF P 94-102-2 [47] [48].

B.13.3 - Issues involved Design and sizing of a transition structure between the earthworks and the road which, for a given upper part of earthworks or of a subformation, will produce the mechanical, geometric, hydraulic and thermal characteristics taken as hypotheses in the design of the road. This structure must simultaneously provide a response to short term objectives in relation to the road’s execution stage (site traffic, for example), and long term objectives in relation to the period of operation.

B.13.4 - Influential parameters • classification of the upper parts of earthworks or subformation and frost-sensitivity of the constituent materials; • hydrology and hydrogeology on site (drainage, etc.); • nature and condition of materials envisaged in the technical and economic plan to create the capping layer, in due consideration of the possibilities of the site, possible borrowings and local resources; • envisaged meteorological conditions, depending on time of construction; • execution phasing of the upper parts of earthworks, the capping layer and the road; • site traffic (supply of road materials). The combination of the upper parts of earthworks with the capping layer [PST-CDF] must be designed to meet the requirements of site traffic; • reference frost index IR (adaptation to the capping layer); • environmental constraints (dust, subsurface water, etc.).


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B.13.5 - Execution phasing for a capping layer Execution phasing


Site preparation

• validation of studies; • creation of an actual-scale test site if required; • administrative procedures (classified facility).


• verification of materials and of procedures for execution; • possible execution and definition of the contents of the validation test.

Execution

• nature and condition of materials before and after production or treatment stages; • verification of the various stages of treatment; • compaction; • surface protection; • feasibility of execution in accordance with meteorological conditions; • set out the risks vis-à-vis statistical data relating to frost; • reflections on reception criteria and procedures; • reflections on conditions for enactment of circulation.


• calibration and verification; • validation test to be carried out or adapted in accordance with the size of the site. The objective of this test is to provide indications to the construction manager on the contractor’s ability to reach the level of quality required.

see GTR Technical Guide to Embankments & Fills section I chapter 3 and section II Annex 3 see GTS Guide to Treatment of Soils part C and annexes

Meteorological statistics. see sections 2 and 3 of this guide.


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C – Special structures and particular points C.1 – Embankments & fills next to structures C.1.1 - Area concerned • embankment behind an abutment; • embankment next to a retaining wall; • embankment around a metal or concrete duct (excluding reinforced earth structures).

C.1.2 – Reference documents • • • • •

Creation of embankments/fills and capping layers (GTR Technical Guide to Embankments & Fills) [10]; Embankment work on trenches and road reworking [12]; Ordinary technical clauses concerning metal ducts [22]; Retaining walls [23]; Conduits – Setra Information Note No. 12.

C.1.3 - Issues involved The materials used must not cause large amounts of dust around the structure ==> restriction in terms of the natures of materials which may be used. The embankment to be constructed is small, and this creates implementation difficulties ==> the materials to be chosen must be easily compacted or specific techniques must be used (hydraulic filling, or packing in the case of embankments/fills to run ducts, for example). Mechanical, chemical, electrochemical and biological corrosion must be considered when materials are next to a metal or reinforced concrete structure (see guide for metal ducts, for example). For embankments/fills next to duct arches, the material will be in abutment, and so the modulus must be sufficient (for example, EV2 > 40 MPa).

C.1.4 - Solutions normally recommended In general, to provide an overall response to the various particularities described above, gravel must not be used. The DCE thus accepts materials classed B3 or D2 which have little sensitivity to water or none at all, and have good internal friction (ϕ‘> or =35°) and a good pressure meter modulus (E = 20,000 – 40,000 kPa). Other materials may also be used depending on site cases: sandy materials classed B1, B2 or D1. In this case, the characteristics to be taken into consideration for the contents of the structure are lower: ϕ‘ = 33 - 35°, E = 10,000 – 20,000 kPa.


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Where water may enter the structure through joints, the use of very fine scour-sensitive and erosion-sensitive sand must be avoided, unless particular stipulations are drawn up for the structure. Materials sensitive to water, sand or gravel containing shaley fines and fine soil are to be excluded on principle, unless appropriate preliminary treatment is carried out. This is the case of fine soils low to average A1 to A2 with plasticity rating that are treated with quicklime In such cases, impose a minimum proportion of CaO (usually 2%), grinding mixture 0/20 mm minimum or B2, B4 and B5 soils treated with cement or a hydraulic binder for roads (LHR) (usually at least 3%). However, hydraulic binder or cement solutions often eventually lead to the creation of a rigid block, and so consideration must be taken of the following precautionary measures: • verification that the embankment support has a low deformity potential; • make arrangements for a rigidity transition zone in relation to the general embankment.

C.1.5 - Implementation As a general rule, compaction conditions should be imposed in accordance with the GTR Technical Guide to Embankments & Fills compaction tables [10] and the trench embankment construction guide (GTT Technical Guide to Earthworks) [12]. Specific precautions, however, must be taken in the area immediately around the structure. The construction stipulations in Sétra guide for reinforced or cantilever retaining walls will be used, and the main provisions are set out below: Vibrating rollers classed below VM3 must be used parallel to the wall at minimum distance d > (0.5 + H/10) in meters, with H the total height of the wall. Vibrating rollers classed above or equal to VM3 and heavy tires must be used at a distance which means they do not exert any influence on the structure within the limits of Coulomb’s corner (calculations to be carried out by taking the slide plane angle with horizontal plane = π / 4 + ϕ / 2), but restricting this minimum distance to 2 meters (see figure 11). Compaction in the immediate surroundings of the structure will then be carried out by small vibrating roller units, vibration plates or tamping machines, the use of which will be as per the GTR Technical Guide to Embankments & Fills or, for certain structures, by hydraulic filling, requiring the use of materials with no components larger than 50 mm.

C.1.6 – Special systems Where water can percolate into the embankment, and in the case of water tables, it is advisable to use a drainage system to prevent hydrostatic pressure on the structure and water flows around joints. In both cases, depending on the type of structure, drainage facilities must be envisaged (see Sétra guides for ducts and for retaining structures) [22] [23].

Figure 11

Zone de compactage interdite aux compacteurs lourds


Compaction area not to be used by heavy rollers

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C.2 – Development of cut/embankment boundaries C.2.1 - Area concerned cut/embankment passage area on the project’s longitudinal section cut/embankment passage area on the project’s cross section

C.2.2 – Reference documents •

General Technical Specifications (CCTG) section 2: general earthworks [49];

•

Regulation NF P 11-301 (12-94) [46];

•

Organization of quality assurance in earthworks [9];

•

Catalog of type structures for new roadways [1];

•

Technical guide to soil treatment [13].

C.2.3 - Issues involved To ensure continuity of the bearing capacity of the “earthworks” subformation. To ensure drainage in the facility as executed. To prevent runoff water in the final infrastructure from stagnating and weakening the facility as executed. To ensure connection caused by coarse topographical discontinuity (example of an embankment/cut trajectory on a cliff). The objective of development of the cut/embankment boundary is to break free of the geological layer beneath the topsoil, whose bearing capacity is insufficient for the capping layer and pavement courses. When there is a considerable slope on the natural ground, the trajectory from cut to embankment is covered in a few meters. The facility can therefore be provided for over this distance. When the slope on the natural ground is largely similar to that of the longitudinal section, the capping layer + pavement courses block rests on terrain which is generally mediocre (underneath a humus layer). Development of the trajectory from cut to embankment must therefore be executed over dozens of meters (several sections) to ensure continuity at the bottom of the cut for the bearing capacity of the embankment’s subformation. It is therefore much more difficult to treat this zone since the slope of the natural ground will be similar to that of the longitudinal section.

C.2.4 – Recommended solution The solution normally adopted, if the material encountered cannot provide a bearing capacity equivalent to that of the subformation of the embankment and adjacent cut, is to replace it with materials at least equivalent to those implemented on the embankment. The thickness of this substitution must produce the bearing capacity of the earthworks subformation set out in the Particular Technical Specifications (CCTP). In accordance with the underlying soil encountered, the thickness of this substitution may be: • zero (compaction of the natural ground stripped or treated); • limited to the upper parts of the earthworks; • increased, so that the upper section + purge embankment couple reaches the bearing capacity set out in the Particular Technical Specifications (CCTP).

C.2.5 – Development of a cut/embankment boundary in the project's cross section The solution in this case is identical to the longitudinal section.


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Construction stipulations Length of development of the cut/embankment boundary: The choice of length depends on: • the bearing capacity of the geological layer under the topsoil; • the difference in the gradient between the natural ground and the longitudinal section. Development may thus be carried out over one section or several.

Execution methodologies Substitution of materials identical to those on the upper parts of the earthworks on the adjacent embankment This solution is applicable when there are no drainage problems involved with the substitution.

Substitution of materials which are not water-sensitive This solution is necessary when drainage problems are encountered, where gravitational flow requires a specific study. Here this substitution will be associated with a special drainage system to take away water ingresses at the construction and operation stages. The method used will be implementation of chevron drainage trenches, where the outlet will be the collector at the foot of the cut slope, and the ditch at the foot of the embankment slope. The materials used, for example, will be D2 or D3, either from the site or external quarries.

Substitution of treated materials When the cuts do not contain materials classified D2 and D3 and the cost of supplies from external quarries is prohibitive, it is possible to treat the materials in situ or replace them with materials which have been rendered non-sensitive by treatment with air-slaked lime or hydraulic binders. There are some useful references in the technical guide “treatment of soils” [13]. Special drainage may be called for if there is a sporadic risk of water penetrating beneath the subformation. If water ingresses are generalized, the preferential choice will be granular substitution materials.

Treatment of materials in situ with no substitution When the quality of the materials in place augurs good results after treatment with air-slaked lime or hydraulic binders, substitution is of no use, and we can merely treat the cut/embankment trajectory over one or two layers, depending on the desired result.

Choosing the thickness of the substitution This will be adapted in accordance with the class of the earthworks subformation (AR1 to AR4) set out in the Particular Technical Specifications (CCTP). In generally, the thickness of this substitution is set at 1 meter, relying on the quality of the materials to obtain the required performances.

Trajectory of a cut/embankment through or along a vertical wall (case of the cliff) This is a special case, focusing particularly on the quality of the connection between the embankment and the cut, and less so on the road bearing soil, if the problem has been solved in the preceding stage. Here, we will refer to the recommendations in “Embankment on a slope”, taking due note of the fact that the width and length of the keyways are essential to attenuation or even elimination of differential settlements between the two structures. In the event of any doubts as to the final result or simply due to precaution, in difficult situations reinforcement should be planned for surface structures (upper part of earthworks, capping layer) by using, for example, layers of geotextile that provide reinforcement, and a suitable road structure that allows repair or reinforcement without excessive related requirements or constraints.


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C.3 – Compaction of embankment edges C.3.1 – Area of application The edges of embankments/fills.

C.3.2 - Reference documents Creation of embankments/fills and capping layers (GTR Technical Guide to Embankments & Fills) [10].

C.3.3 - Issues involved A non-compacted slope can be unstable (risk of peeling, etc.), and a classic compacting is not possible, since compacting units have difficulty negotiating safe access on the edges of embankments/fills.

C.3.4 – Recommended solution – advantages/disadvantages One of the following two methods is generally used to compact the edges of the embankment:

The excess embankment method Implementation of extra width means the compactor is not obliged to make its approach from the edge of the embankment (see figure 12). The extra width of materials added to the embankment is around 1 meter beyond the final gauge, which means that about 0.60 m of extra material has to be removed subsequently on the slope for a gradient of 3/2.

Use of a reverse gradient (transverse W profile) (see figure 13) This method involves the creation of a reverse gradient on the edge of the embankment which is the width of the leveler blade. The gradient is around 4%. The reverse gradient is not enough in itself to allow the compactor to compact the ground up to the edge of the embankment, and so a small extra width of 0.50 m is required. This represents a thickness of 0.30 m of material to be removed from the slope. The advantage of this method is that it minimizes runoff erosion on the slope. The main disadvantage of this method is drainage, which must always be arranged in the case of gentle longitudinal gradients to prevent any risk of water penetrating the embankment. At the end of the day, the embankment will be bled to direct water down to temporary drainage channels that are provided as the earthworks progress.

Figure 12

Figure 13: General embankment profile

Figure 12 Remblai Environ 0,60m pour une pente de 3/2 Pente d’environ 4% Sur-largeur de matériaux à enlever du talus Environ 1 m


Figure 13 Embankment Approx. 0.60 m for a 3/2 gradient Gradient around 4% Excess width of materials to be removed from slope Approx. 1 m

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Demi-profile

Half-profile

Largeur de lame Environ 0,30m Environ 0,50m Demi-largeur finale de la plate-forme

Width of blade Approx. 0.30 m Approx. 0.50 m Final half-width of platform

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Formation of the slope – Removal of excess materials Excess materials are removed when this does not pose any risk of disorganizing the slope (rocky embankments/fills). These materials must be removed from the structure either as it is being built or when the embankment has been completed. Water-sensitive soils may be reused on the embankment if their moisture condition allows. A hydraulic shovel is traditionally used to dig up the slope along the surface of the embankment, in sections of between 3 and 5 meters in height, in accordance with the characteristics of the shovel. This operation will require experienced employees capable of forming the final profile (with no need for additional operations). Care will be taken to leave part of the excess embankment in place at the top of each section, with a 2/3 gradient, when the materials are removed. The following layers will draw support from this buttress remaining in position, allowing the extra width imposed for the upper section to be respected.

C.3.5 - Mode of execution It will be observed that telescopic shovels, Gradalls or bulldozers can remove excess material for a greater embankment height (see figure 14).

C.3.6 – Checks and implementation Checks on compacting will be carried out using: • the overall e-Q/S method, with some additional isolated measurements (gamma densitometer, penetrodensitograph) to ensure low density dispersion in the cross section; • direct density measurements (gamma densitometer) or indirect density (penetrodensitograph) in sufficient numbers to allow reliable references to be established.

measurements

A check will also be run for the extra widths, and for the reverse gradient in the second method. A check will be made to ensure that the compactor has conducted the sweep properly, particularly on the approach to the edges of the embankment.

C.3.7 - Remarks Particular attention must be paid to the risk of smoothing of slopes by machines equipped with blades. Smooth surfaces can cause difficulties subsequently in terms of adding topsoil to the slope. It is preferable for the bulldozer to work in the direction of the line with the highest gradient. The caterpillar tracks left will create anchorage for the topsoil and a trap for water and fines, and this will encourage the growth of vegetation.

Figure 14

Matériaux à retirer Environ 1,2 l Remblai Collection « Les outils” – Sétra

Materials to be removed Approx. 1.2 l Embankment – 104 –

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C.4 – Purging and substitution C.4.1 - Area concerned Execution tasks as preliminary work. Bearing soil on road embankments/fills within the main structure (definition: structure required for functionality of the operation, within the construction limits of any road surface). Materials in place within the final profiles (subformation and slope of cuts) which do not guarantee the quality required for the main structure as completed. Development of the cut/embankment trajectory.

C.4.2 - Reference documents •

Regulation NF P 11-301 [46];

•

Section 2 – General earthworks (articles 5.6 and 6.7) [49];

•

Organization of quality assurance in earthworks [9];

•

Guide to drafting the Particular Technical Specifications (CCTP) for earthworks [19].

C.4.3 - Definition of purging Purging must be understood as the local extraction and evacuation of a maximum volume of 100 m³ of materials or products in the subformation and on cut slopes or bearing soil on embankments/fills which do not have the following: • sufficient quality for reutilization in road embankments/fills and capping layers in the main structure; • the required quality in terms of deformability or bearing capacity, or permeability to ensure stability in the main structure. The material extracted from the area purged will be taken for final deposit or, following an agreement with the construction manager, it will be reused in the surroundings of the main structure (landscaping embankment, earth mound barrier, etc.). Regardless of whether the purges are already planned and localized, or unplanned, the contractor will subject the methods used for purging and filling for approval by the construction manager.

C.4.4 - Definition of a substitution 3

A substitution must be understood as an operation which involves, per unit volume > 100 m : • location within the substitution area; 3 • dimensional characteristics such as quantity (volume > 100 m ); • extraction and removal of materials in place in accordance with purging criteria; • work methodology (extraction, filling, compaction); • the quality of the materials to be implemented instead of the materials to be substituted, judged insufficient for the level considered; • the required levels of quality set by the contract; The technique known as substitution must be fully defined in the Particular Technical Specifications (CCTP), and the construction manager must define a special substitution work price in the prices specification. This operation mainly concerns the upper parts of earthworks on cut/embankment interfaces.

C.4.5 - Issues involved The main problems are: • quantification of purging during the DCE stage; • evolution of the material in place; • the sizing of the purging for the quality required; • the filling technique involved in the purging process; • settlement method for this service. Collection « Les outils” – Sétra

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Quantification of purging during the DCE stage Quantification of the purges depends on the following parameters, the risks of which should be appreciated: • the degree of precision of geotechnical and hydrogeological studies; • knowledge of the changeable or unstable nature of the local materials; • the probable meteorological conditions on site, and in sensitive areas in particular; • the earth movement plans to be implemented in accordance with climatic periods and soil types; • the quality of site drainage and sewerage.

Evolution of material in place The evolution of a material in place is inherent to the following: • intrinsic characteristics of the material and its fragmentable and degradable nature following exposure to climatic agents; • increases in water content, and thus lower bearing capacity (waterproofing and/or drainage and sewerage problems); • heavy earthworks machinery moving over types of soil with the humidification conditions and characteristics described above ("excess compaction in sensitive areas”). After the bores carried out by the contractor for his earth movement plan or the discovery of a sensitive material after stripping of topsoil, the contractor identifies purging areas. He submits these for approval by the construction manager, and takes all necessary action to prevent further “accidental” purging. When considerable traffic in terms of earthworks machinery purges the contents, particularly in terms of the subformation of cuts, it is advisable for the construction manager’s DCE to make arrangements for the last 50 cm before the subformation to be worked over just before implementation of the capping layer.

Sizing of the purge required The dimensions of unplanned purging depend on the following:

On the surface: • on the horizontal dimension of the area which is unstable or contains non-reusable materials; • on the extraction and compacting material set out in the Particular Technical Specifications (CCTP) for purging or, failing this, on the means available on site. In terms of depth: • on the thickness of the material to be purged, following examination of the local bores; • for the contractor, on the customary quality of the platform considered during the construction works stage; • for the construction manager, on the quality required after filling has been carried out on the area purged. Consideration of all these factors, particularly the quality required to fill the area purged, will allow the construction manager to accept the methods of execution of unplanned purges proposed by the contractor. For planned purging and substitution which have been accurately identified in the geotechnical study, the Particular Technical Specifications (CCTP) must set out the location and size of each.

Technique used for filling purged sections The filling technique will depend on the size of the area purged, especially in terms of depth and accessibility, which may lead to extra earthworks on reusable materials. The procedures for filling are those normally employed for low-mass embankments/fills (see technical guide to trenches - GTT Technical Guide to Earthworks) [12]. The level of performance must be sustainably equivalent to that of the section of the structure to which the work belongs. After filling, the purge must not constitute a water trap which will contaminate the bearing soil in the area purged, or the embankment construction materials used. If this risk exists, a drainage facility must be provided after purging. The objective of the filling technique for the area purged must also be not to constitute a hard point with respect to the rest of the platform, or an excess load on unstable soils, particularly on slopes where there is a risk of earth slides. With respect to the filling technique in water (pond purging), the main stipulations advocated for water filling Collection « Les outils” – Sétra

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procedures will be implemented. The filler materials in this case will be preferably D2 or D3. The filler materials will be natural or treated with lime and/or hydraulic binders, especially in moist or floodable areas. Natural materials will be from the site, if the quality of the materials available on site matches the conditions for reuse in purging set out in the Particular Technical Specifications (CCTP), or from external quarries).

Method of settlement Purging services are often paid by the project owner (solution recommended by section 2 of the General Technical Specifications (CCTG). Purging work is compulsory as part of preliminary tasks, embankment work and the final stages of cuts, when the natural soil in place, or reworked soil, or deposited products cannot meet the quality conditions required for the structure to be built. Purges of site roads in connection with maintenance are the responsibility of the contractor. When the DCE estimate does not include the price of purges, or a remuneration system for purges, if required, the contractor must request an additional purge price during the construction works stage. The price will thus depend on the following: • whether or not there is any possibility of deposit in the land requirements, and transport distances to remove the purge materials; • means not available on site to be implemented to carry out purging operations; • the urgent nature of activities and incidence on organization of work; • the type of filling material for the purging operations and inherent constraints; • any drainage facilities required. Remuneration for unplanned purging work must be covered by special examination on a case-by-case basis. Examples: • in the event of lower bearing capacity due to the absence of a drain trench in the DCE, purges are the responsibility of the project owner; • in the event of lower bearing capacity due to faulty temporary drainage during the construction works stage, purges are the responsibility of the contractor.

C.4.6 - Recommended solution 1) Conduct an in-depth examination of the geotechnical and hydrogeological reports and the geological profile. In embankment zones, identify sensitive sectors of natural ground which are likely to entail purges. Proceed in the same way by examining the geological level of the final profile of the cuts (make arrangements for drainage trenches or shields, not purges, on unstable slopes). Consider the climatic periods for carrying out each construction works stage (work on natural ground, finishing of the final cut profiles). Improved management of program authorizations (AP) would eliminate a large number of site problems in relation to inclement weather. On the basis of the above, work out the total plausible surface to be purged, and identify profiles which require purging. Quantify the purge volume on the basis of a hypothesis of maximum depth 1 m. 2) Preferably provide a purge remuneration system in the DCE, and a substitution price. The remuneration system for planned and unplanned purges will be based on the proposals A, B, C and D below: A1) Include, in the site installation price, as the means required on a constant basis for minor tasks (sewerage, drainage trenches or shields, cut/embankment area, etc.), the purge material and its transportation (state a maximum distance) at the purge site (to be stated in the prices specification). The advantage of this stipulation is that it provides a response to the urgency of certain operations; A2) Remuneration for the purging service will include, for a volume ≤ 100 m³, cuts, removal and implementation outside the main structure of the materials extracted (to be specified in the prices Collection « Les outils” – Sétra

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specification when the contractor reuses the site materials for filling work). B) Extraction, transportation whatever the distances involved, and implementation of site materials as agreed by the construction manager. C) A price for supply and implementation of filler materials for purging when site materials are not reusable. D) The need to use other market prices for geotextiles and drainage systems. Concerning remuneration for substitution, this price will be fully identified in the BP prices specification, and will account for all services, including those inherent to filling materials and to drainage constraints. 3) During the stage of preliminary work and work on the main structure, reports are to be drawn up jointly by all parties concerned on the platform's drainage facility and the condition of the bearing soil on embankments/fills and the subformation of cuts. This constitutes zero condition for the quality of the support (additional bores carried out by the contractor may be put to some use). 4) In relation to purges, the following operations must be carried out: •

mark out and isolate the purging area from the rest of the site for safety reasons;

• shovel bores to identify, in accordance with the GTR Technical Guide to Embankments & Fills, the nature and thickness of the materials called into question, and to verify whether or not there are any water ingresses; • before purging operations, purging earthworks must be drained to ensure the long-term durability of these works in the event of water circulation in the soil; •

terracing of the purge area avoiding the excavations site;

• implementation of a geotextile on the entire excavation area if there is any risk of contamination of the filling materials; • preferential filling, with high quality site materials, of the entire purge area (1 layer) if the compatibility of the compacting material with filling materials is verified; • in the event that implementation over a single layer is incompatible with the compactor, create two layers, the first of which must not be less than 70 cm. In this case, an access or exit ramp for the compactor will be created, and compaction energy will be low in accordance with the GTR Technical Guide to Embankments & Fills. • With respect to the finished purge level, envisage extra thickness of the filling material to improve the effectiveness of the compactors, and then level off the area to the final profile.

C.4.7 - Remarks In the case of sites containing soil treated with lime or hydraulic binders in the contract, the area to be purged may be treated in situ, although the technical and financial feasibility of this operation must be examined. Particular attention must be paid to the thickness to be treated and the methodology of the treatment. If this is very different from the treatments set out in contract, the service will be more specific, and so a special price must be set out in the specification.


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C.5 – Extra-large embankments/fills C.5.1 - Area concerned Extra-large embankments/fills are understood as maximum height in excess of 15 meters. Embankments/fills 10 - 15 meters high are considered as ordinary embankments/fills, and in these cases the stipulations of the GTR Technical Guide to Embankments & Fills for embankments/fills over 10 meters are applicable. Construction of motorways or railway lines in recent years has led the section in charge of studies to reflect on the subject, and so a number of research programs are currently ongoing, especially in relation to the laws governing the behavior of compacted and unsaturated soils.


Creation of embankments/fills and capping layers [10];

•

Treatment of Soils (GTS Guide to Treatment of Soils) [13];

•

Study and Creation of Embankments & Fills on Compressible Soils [8];

•

Recommendations for the Design and Execution of Road Embankments & Fills - AIPCR [18];

• Stability of slopes on cuts and embankments/fills – Special issue of LPC Public Works Research Laboratories [62]; • Recommendations for the use of geotextiles and geomembranes by the CFG (Comité Français des Géotextiles et des Géomembranes) •

Organization of quality assurance in earthworks [9].

C.5.3 - Issues involved Extra-large embankments/fills are considered as structures since their building specifications combine the conditions for implementation of ordinary embankments/fills and stability conditions which can substantially alter the design of normal construction criteria: the choice, the arrangement and implementation of materials in the embankment thus become decisive factors. They must have a structural definition in a project where considerations are essentially geotechnical: the alignment sections must clearly show the locations of the various materials to be used to build the embankment, with details of their classification in the GTR Technical Guide to Embankments & Fills, or their moisture condition. While certain issues are common to both categories, especially issues relation to the bearing soil, other issues concern this type of structure, or at the very least cannot be ignored. The difficulties involved in the rectification of structural damage are substantial, in view of the technical and economic challenges they may involve. Topographical modification of a site by the construction of an extra-large embankment amplifies the conditions relating to local balance, usually unfavorably. The decision to build an extra-large embankment depends on a number of different factors - stability, environment, hydrology, etc. – and this could lead to the choice of building such a structure, a bridge or a viaduct.

C.5.4 – Studies to be arranged Methods and means The substance of the study must focus on the issues of choice of borrowing materials and the conditions of stability of the structure and its support. Investigation at the structure, using mechanical bores of the ground which constitutes the embankment’s support, must be at a height at least equivalent to that of the embankment, due to the thickness of the ground that carries the weight of the structure. Following the axis of the longitudinal section, we can space the bores at intervals of 40 - 100 meters, in accordance Collection « Les outils” – Sétra

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with the characteristics of the site as pre-defined on documents and the difficulties of access around the boring areas. The mesh can be tightened further if more precision is required. Cross sections must be established by preferential choice of lower points on the natural ground and areas suspected of containing anomalies. This investigation will require sample bores, pressure meter bores, and penetrometric and scissometric bores for soft soils. Other types of bore tests may be carried out depending on the context of the study site and the specific nature of the issue treated, among which destructive bore tests to detect spaces at a certain depth, auger drill tests for soils outside the water table, and mechanical shovel for low-depth investigation.

Lab tests In addition to classic geotechnical tests, tests may be carried out to ascertain the mechanical and hydraulic behavior patterns of soils in the embankment and in the bearing soil.

C.5.5 – Contents of a design study Studies are generally divided into two stages, as follows: • the stability study - in other words, the stability of the bearing soil, with the embankment considered as an extra load, or the embankment taken with supposedly uniform mechanical characteristics, in the knowledge that its definition is not known at this stage; • the overall stability study focusing on the stability of the embankment, with consideration of measures previously taken to reinforce the bearing soil if the first study demonstrated a need for this. The first study ought to solve problems relating to: • the speed of consolidation of the bearing soil; • the speed of erection of the embankment (care taken with phasing); • hydrogeological incidence; • the introduction of techniques for improvement or reinforcement if geotechnical conditions make this necessary. The second study ought to allow definition of an earth movement to obtain stability and the capacity to: • set out the structure of the embankment and any internal drainage facilities; • state any external features required to secure the stability of the entire structure and its base. Beyond highly compressible bases and unstable slopes which should be treated separately, the loads caused by extra-large embankments/fills can, in layers which are normally not very compressible, lead to stresses much higher than the stresses of preconsolidation σ’p. By way of example, an embankment of height 32 meters and slope gradient at 1(V) for 2 (H) creates settlements calculated in the bearing soil of around 0.50 meter in the axis, in a homogenous environment, for a pressure meter modulus of around 25 MPa defining high-quality soils such as categories B2, B5 or B6 of the GTR Technical Guide to Embankments & Fills, and for a thickness of “compressible” soils of 40 meters. It should be noted that at this depth the stress is still considerable (75% of the vertical stress σv applied on the surface). The calculation software makes use of the following: • the sliding surfaces theory (calculation to break point); • the finite elements method (calculation of stresses and displacements); • the layer consolidation theory (estimation of vertical displacements). Structures in this type of medium are generally not very sensitive to seismic phenomena. In sensitive areas, however, the approach drawn up by the French Paraseismic Association (AFPS) will be applied. The results obtained using the finite elements method in several hypotheses involving relatively simple structures show that: • the layers stiffened by hydraulic treatment at the base of large embankments/fills may constitute the center of critical strains due to considerably buckling in the bearing soil, even when its characteristics are quite favorable; • areas which enter the sectors of permanent deformations fastest (plasticity) are: the edges of slopes, locations with sharp angles (bottom of slopes, initial section of bench terraces) and areas of contact embankment / base soil. Collection « Les outils” – Sétra

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Utilization of the finite elements method is not necessary in all hypotheses, and is not always possible (if there is insufficient data). However, its use may provide valuable information for complicated shapes or structures following the establishment of parameters for the model after lab tests (if these can be performed) and in situ tests that are appropriate for the problem posed. In general, modeling of a structure using this method is recommended whenever knowledge of the fields of vectors can better justify a given situation. For ordinary situations with no specific features, the methods normally employed for stability studies are sufficient to deal with most problems (pressure measurement, oedometric and others, etc.). Many very different kinds of technology are used to reinforce the stability of a site. Below we have set out four frequent means applied to the embankment to improve the overall content of the structure: • partial lightening of the embankment; • earth reinforced with geotextiles, nails, blades, etc., applied to the enhancement areas indicated in the study;

• side bench terraces next to the slopes of the actual embankment when the land requirements are sufficient; • treatment of the embankment with hydraulic binders, verifying the validity of the level of the stresses. The design study must cover the following: • definition of systems for reinforcing the bearing soil if necessary; • definition of the embankment's structure: dividing the cross section into areas of identified materials, showing any drainage systems; • definition of the geometry of the road embankment (gradients of the slopes, bench terraces, secondary embankments/fills against the main embankment); • definition of hydraulic structures to collect runoff water and structures to restore the hydrographic network.

C.5.6 – Guidelines for construction stipulations and choice of embankment materials This technical document does not cover the organizational section of a contract or a site. Specialist documents are available in the guide “Organization of quality assurance in earthworks”, quoted in “references”.

The construction stipulations for preparation of the bearing soil In the presence of compressible soil, the technique for erecting an embankment in successive stages which is considered first may require long building periods, and this is often incompatible with the economics of the project. What is true for any embankment is all the more true for an extra-large embankment. There is also the question of using the abovementioned improvement techniques (lightening the embankment, reinforcement of the structures) and, in parallel fashion, removing and partially or totally substituting the layer, following a technical-economic examination, by a variety of methods (earthworks, driving back soft soil, etc.) (see guide: “Study and Construction of Embankments & Fills on Compressible Soils) [8]. In most cases, there will be no need to strip the bearing soil as such from a large embankment, the only possible exception being stump extraction in the case of large items and cleaning of the platform. Stripping operations often prove counter-productive since they reduce trafficability conditions. If the study has detected non-negligible spaces in the subsoil, these should be pre-treated using a method adapted to the problem (filling, mechanical reinforcement of gaps). In relation to this point, in due consideration of the probable large number of stresses in relation to the anomaly after loading of the embankment, the operation must often be subjected to a specific stability study (see “Crossing an area of underground cavities”) for gradients which are often lower than the gradients of normal embankments/fills. Bonding an extra-large embankment to its base may require construction of keyways.


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The construction stipulations for the main body of the embankment Before any zoning diagrams, some answers should be provided for a number of technical points concerning the behavior of blocks found in the earth. Any fissuring in an embankment or part of an embankment is detrimental to its contents, and so it is advisable, before a certain type of material is adopted, for its mechanical performances to be appraised and compared with the stresses and deformations calculated as the most unfavorable to the layer. To avoid subsequent inconveniences in relation to road land requirements caused by structural damage on slope edges (permanent deformations), it is better to envisage an extra safety width as a road shoulder. It is not the custom to build an internal drainage system inside the main body of the embankment - experience shows that structures built with extremely heterogeneous soils from the hydraulic viewpoint have created serious setbacks. Larger embankments/fills expose non-negligible surfaces to inclement weather and therefore to infiltration water which reaches the most permeable sections of the embankment and eventually causes instability on the edge of the slope when it dries or overflows. On this point, the harmful effects of past applications of the technique known as “sandwich” layers - alternative sandy and shaley layers - should be borne in mind in relation to the behavior of the structure over time. The use of geotextiles and geocomposites chosen by their destination (separation, drainage, etc.) offers the advantages of the simplicity of the application, and probably also the advantage of costs in comparison to granular material performing the same function. We will attempt to limit the drainage facilities to areas of the structure which are deemed to be sensitive and where there is a long term risk of accumulation of water. Thus, in relation to the future behavior of the structure, we must obviously seek to build the most homogenous embankment possible, even if this means modifying the optimum movement of earth. The base of the embankment in contact with the natural ground is naturally used to recoup infiltration water in the embankment. This could possibly be envisaged in addition to the drainage network through the embankment, using large staples if necessary (this is especially true in the case of an embankment built on gradients) and accelerating consolidation of the layers if they produce interstitial pressure due to the stresses and presence of the water table at low depth. Areas of slopes and bench terraces are the most unstable sections of the embankment. The usefulness of bench terraces and their design for the purposes of maintenance must be closely examined. They are not always a guarantee of stability, and in the long term entail the risk of local ruptures following water infiltrations in water-sensitive areas. From the mechanical point of view, slopes with uniform gradients are very often preferable to profiles with bench terraces, if we consider that a slope with a maximum gradient of 26 degrees with respect to the horizontal plane (gradient at 1V/2H) does not pose any major problem to operations by current maintenance units. Interfaces between the slopes of the embankment and the adjacent confinement depots are to be treated as heterogeneous embankment sections. Water ingresses stemming directly from runoff and infiltration through the road infrastructure may be solved by a device combining a waterproof membrane and a drainage system above it. This structure is implemented at the top of the structure (upper part of the earthworks, capping layer), and a replanted central reservation must be protected in this way.

The materials used on the main body of the embankment Choice of materials relates in particular to the availability of cut materials found on site. With reference to the GTR Technical Guide to Embankments & Fills, a document whose scope of application is clearly set out in its presentation, the soils which may be used on embankments/fills of over 10 m, in precise meteorological and site conditions, are listed in the tables found in the guide. Moreover, the document shows that the reutilization of certain materials, in the case of larger embankments/fills in particular, is subject to a specific study. The choice of materials relates strongly to the combined structure of the main body of the embankment and its base. The design of the structures will be priority-defined in accordance with the resources available on the Collection « Les outils” – Sétra

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alignment or nearby, and the recommendations for use. In connection with what is now known of the behavior of soils within a block of earth, the choice of materials may be adapted to reasons which do not solely take account of the recommendations of the GTR Technical Guide to Embankments & Fills. A priori, no soil qualified by the GTR Technical Guide to Embankments & Fills as usable may be rejected if its utilization in a certain area of the embankment is technically justified, although it would be normal to focus initial supply sources in the direction of materials in this document which entail no embankment height restrictions.


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For these structures which involve both problems of implementation and stability, the dual classification by the GTR Technical Guide to Embankments & Fills and the LPC Public Works Research Laboratory is recommended for identification of the soils. We should mention that the behavior of soils in non-saturated media after compaction is currently being examined in research studies. The table below shows the categories of soils whose usage does not bring into play the height restrictions set out in the GTR Technical Guide to Embankments & Fills. Soils in categories B1, B3, C1B1, C1B3, C2B1, C2B3, D1, D2, D3, R21, R41 and R61 are to be preferably reserved for areas of drainage and mechanical stabilization of the lower section of embankments/fills. The lower section is understood as a height of around 20% of the total height of the embankment, and minimum width 5 meters for the edges of the embankment. In certain cases treated soils can also perform mechanical stabilization functions on the edges and at the foot of slopes. The normal definitions setting out the quality of materials on an embankment as components of a contract (particle size distribution, cleanness, hardness, etc.) must be completed with mechanical criteria (shear strength, settlement, swelling, etc.) and hydraulic criteria (permeability). Experience shows that moisture exchanges between materials making up the main body of an embankment form the origin of the main pathologies directly attributed to it. Meteorological situations

Categories Fine soils

Granular soils

A1h, A2h, A3h* A1m, A2m A1s, A2s

=, =, =, -

B2h, B4h, B5h, B6h* B2m, B4m, B5m, B6m* B2s, B5s, B6s* B4s

=, =, =, +, =, -

B1, B3, D2, D3

Soils containing rubble

All situations

C1A1h, C1A2h, C1A3h* C1A1m, C1A2m C1A1s, C1A2s C1B2h, C1B4h, C1B5h, C1B6h* C1B2m, C1B4m, C1B5m, C1B6m* C1B2s, C1B4s C1B5s, C1B6s* C1B1 C1B3 C1D2 C1D3 C2A1h, C2A2h, C2A3h C2A1m, C2A2m, C2A3m C2A1s, C2A2s, C2A3s C2B2h, C2B4h, C2B5h, C2B6h C2B2m, C2B4m, C2B5m, C2B6m C2B2s C2B4s C2B5s C2B6s C2B1, C2B3, C2D2, C2D3

Rocky soils

R11 R12h R12m, s, ts R13h* R13m, s*


TC A H

SEE GTR

TC, TR E, A H E, A, H

SEE GTR

No conditions TC E, A H E, TC E,A E, A E, A, H E, H

SEE GTR

No conditions E E, A A, H SEE E E,A GTR A H No conditions E TR E E, TR E

SEE GTR

All situations No conditions As per change in particle size distribution See GTR

R22, R42, R62 R23*, R43*, R63* lime treatment, treatment with a suitable reagent utilization as-is with drying afterwards if necessary sprinkling humidification

All situations +, =, +,=, +, =, + = All situations +, =, =, =, =, =, -

R21 R41 R61

TC TR E A H

= =, = =, +, =, =, +, =, +, =, -

Conditions for use

+ light rain = no rain or significant evaporation - evaporation * use of these soils for embankments/fills over 10 m entails a specific study ( GTR)

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Large embankments/fills induce stresses over and above those which may be caused by any compacting machine. In fact, the overconsolidation stress caused by compacting between 150 kPa and 230 kPa is estimated in accordance with the nature of the material, and the energy expended to compact it (within certain watercontent limitations). This means that materials may certainly evolve in particular demanding areas of the embankment, despite good compacting during implementation. Granular soils, however, have an ability to adapt which ought to secure them a certain amount of balance as the embankment is built, in view of their behavior pattern which relates to density and not time, as in the case of fine shaley soils.

C.5.7 – Monitoring and instrumentation program Like any structure, large embankments/fills must have a monitoring and maintenance program. “Point zero” must be established quite soon after work has been completed. This constitutes extremely useful information, which to some extent provides a “picture” of the finished structure, and is as follows: • drawing up a monitoring/maintenance plan; • implementing sustainable markers as milestones, and carrying out a topographical survey at a large number of points; • drawing up an as-built file. Monitoring must be carried out in the first instance on hydraulic facilities: drains, collectors and drainage channels. Any equipment failures must be quickly followed up with repairs. A visual overall check of the structure must be arranged at least every one or two years, preceded by a topographical survey. An instrumentation plan is not automatically applicable to all operations – it depends on any hazards identified during the survey or evaluated during the construction works stage. This plan concerns issues relating to subgrade and issues relating to the embankment proper. The means and methods are those set out in chapter IV of the guide “Study and construction of embankments and fills on compressible soils”. The list of equipment and its usage is provided here, with the advantages and disadvantages of each. For the monitoring of settlement and water content, two nuclear logging probes may be used - “gammagamma” and “neutron-neutron”. Evaluation of settlement between any two dates and levels of the embankment and subgrade is carried out in accordance with the variation in dry densities.


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Partial output of calculations by CESAR (LCPC). • Hm = 32 m (4 x 8m stages) • mechanical characteristics of B2 soils

• gradients 2/3

Figure 16


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C.6 – Heterogeneous embankments/fills C.6.1 - Area concerned Embankments/fills built with materials of a heterogeneous nature. Enlarging of existing embankments/fills. Core or box embankments/fills. This document takes no account of composite embankments/fills (enhanced, reinforced, lightened, etc.).


Creation of embankments/fills and capping layers (GTR Technical Guide to Embankments & Fills) [10];

•

Treatment of soils with lime [...] on embankments/fills and capping layers [13].

C.6.3 - Issues involved The design of embankments/fills for roads must, in addition to aspects relating to the quantities of materials required for construction, take account of certain qualitative requirements concerning the materials to be implemented, in order to prevent the introduction of heterogeneities which could subsequently compromise the long-term durability of the structures. These heterogeneities may be horizontal, vertical, or multidirectional. They appear if materials with extremely contrasted permeabilities or particle size distributions which are not intercompatible are used on elementary adjacent horizontal layers – for instance, fine shaley materials with sandy or coarse rocky homometric materials. There is a risk of creating one or more areas of perched water within the most permeable material, especially when the slopes have largely non-permeable topsoil (fig. 17). These areas may subsequently create interstitial pressure in the structure’s shaley layers, or cause the slope covering to slide. In the case of long embankments/fills with a descending gradient, there may be genuine upwelling at lower points along the structure. There is also a risk of slow interpenetration of fine soils into the gaps in the coarser material caused by traffic loads (fig. 18), thereby causing settlement and general deformation of the structure. This also occurs from transversal use of materials with extremely different physical and mechanical properties: in particular, this could occur during the enlargement of existing embankments/fills, with the risk that the section added may slide (fig. 19).

Fig. 17

Fig. 18


Fig. 19

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Fig. 17 Remblai multicouche: problème des nappes perchées

Multi-layer embankment: problem of perched water tables

Nappe perchée

Perched water tale

Infiltration depuis la plate-forme et/ou les talus

Infiltration from platform and/or taluses

Emergence

Emergence

Couche perméable

Permeable layer

Couche imperméable

Impermeable layer

Prendre des dispositions favorisant le drainage

Take measures with regard to drainage

Fig. 18 Remblai multicouche: interactions entre sols fins et sols grossiers Mouvement du materiaux fins vers le materiau grossier

Multi-layer embankment: interactions between fine soils and coarse soils Movement of thin materials towards coarse materials

Materiau fin

Thin material

Materiau grossier

Coarse material

Fermer la couche en matériaux grossier au contact des matériaux fins

Close the layer in coarse materials in contact with fine materials

Fig. 19 Elargissement de remblai

Embankment extensions

Ancien remblai

Old embankment

Surface de glissement potentiel

Potential sliding surface

Nouveau remblai

New embankment

Assurer la stabilité méchanique et le drainage de la surface de contact

Ensure mechanical stability and drainage on contact surface

Ancien remblai

Old embankment

Redan (h > 1m) Nouveau remblai (si possible en matériaux plus permeable que l’ancien remblai

Keyway (h > 1m) New embankment (if possible, in materials more permeable than the old embankment)

Matelas drainant éventuelle

Possibility of drainage mattress


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This is also the case during addition to the final structure of large site roads in fine treated materials or untreated granular materials for constant use, when the complement to the embankment is built in untreated fine material. This can cause risks of differential settlements and disparity in the mechanical behavior of the structure, in due consideration of substantial modulus variation. The presence of granular material at the center of the embankment surrounded by finer materials with a low permeability rating could also create water traps (fig. 20). Box embankments/fills with non-binding granular materials or fine untreated low geotechnical quality shaley materials (at the center of the structure, surrounded by treated materials) and core embankments/fills with fine shaley materials or coarser shaley-mar materials treated with lime and/or hydraulic binders and bound into rough clays (fig. 21), represent the kind of embankment where both vertical and horizontal heterogeneities are most commonly found. In this case certain construction recommendations must be observed (see the next section on recommended solutions).

C.6.4 – Recommended solutions As far as possible, the use of materials whose geotechnical characteristics, particularly their permeability and/or mechanical characteristics, show great disparity, should be avoided in construction of a single structure. Implementation of a drainage system in the cut trajectory prevents water accumulating in permeable layers of the embankment from the cut. Water infiltrates the embankment at the upper section of the structure and moves around the permeable layers. It may be removed laterally if a drainage system has been envisaged at the design stage, and if the material used to cover the slopes is not impermeable. Continuity of flow could also be envisaged through the various permeable layers making up the heterogeneous embankment, with water taken away at the foot of the structure. Particularly in the case of a box embankment, there should be proper surface impermeabilization to minimize water infiltrations, and a drainage system at the foot of the structure - a drainage mattress, for instance. In general, all necessary construction precautions should be taken to prevent water infiltrations to the central reserve, and to ensure that all drainage facilities are properly proofed (fig. 22).

Fig. 20

Fig. 21

Fig. 20 Reprise d’une ancienne piste de chantier susceptible de créer un piège à eau

Reworking of an old site track which could create a water trap

Risque de tassements différentiels

Risk of differential settlements

Ancienne piste

Old site track

Circulations d’eaux confinées

Confined water circulating

Compléter à hauteur de l’ancienne piste

Top up to the height of the old site track Fill up with a material with hydraulic and mechanical properties similar to those of the site track

Remblayer les compléments par un matériau aux propriétés hydrauliques et mécaniques proches des pistes Ancienne piste

Old site track

Continuité hydraulique transversale

Transversal hydraulic continuity


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Fig. 21 Définition des dispositions dites “en caisson” et “en noyau”

Definition of box and core arrangements

Disposition dite “en caisson”

Box arrangement

Matériaux non traités

Untreated materials

Matériaux traités

Treated materials

Disposition dite “en noyau”

Core arrangement

To enlarge existing embankments/fills, as far as possible we should use materials which are more permeable than the most permeable materials in the main body of the original embankment. Keyways or any other type of anchorage system should be provided. Other construction stipulations may also be essential – a drainage mattress, for example (fig. 19). During juxtaposed implementation of materials with extremely different mechanical characteristics (rough clay and treated clay, for example), construction simultaneity is of the essence (tipping of materials, compaction) in order to limit interface de-bonding subsequently. When the embankment is to include a former track, it could be a good idea to build the layer or layers laterally to the height of the old track using materials of the same characteristics as the track, in order to minimize differential settlements in particular (fig. 20), laterally – these represent the kind of embankment where both vertical and horizontal heterogeneities are most commonly found. When an earth mound barrier, a landscaping or anti-noise buttress or a deposit lie on the main body of the embankment (providing a heterogeneous unit in fine), drainage should be provided at the interface of the two structures (fig. 23), since the mound barriers and deposits are usually composed of poorly compacted mediocre materials which can act just like sponges and project water into the center of the main embankment.

C.6.5 - Observations Composite embankments/fills consisting of natural and industrial materials (metal reinforcement structures or similar, geotextiles, polystyrene, etc.) or recycled materials (tires, plastic, vegetable fiber, etc.) are subject to special construction techniques. The specific documents must be consulted, and especially the following: • Study and construction of embankments/fills on compressible soils – Technical guide [8]; • Design and execution of embankments/fills for roads [18]; • Ultra-light embankments/fills on compressible soils – Information note [27]; • Utilization of expanded polystyrene in road construction [20]; • Le Pneusol - Information note CD 47 [26]; • Structures in reinforced earth - Recommendations and rules [25]; • Support and embankments/fills in Texsol [28].

Fig. 22


Fig. 23

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Fig. 22 Matériaux non traits confinés

Untreated confined materials

Infiltrations sous chaussées

Infiltrations under roads

Matériaux non traités

Untreated materials

Matériaux traités

Treated materials

Circulation d’eau

Water circulations

Assurer le drainage à la base

Provide drainage at base

Couche drainante en base de remblai

Draining layer at base of embankment

Géotextile anticontaminant

Anti-pollution geotextile

Fig. 23 LE REMBLAI ET LES DEPOTS ANNEXES (merlons, buttes paysagères ou anti-bruit, depots) Protection du remblai principal Dépôt

THE EMBANKMENT AND SECONDARY DEPOSITS (ground earth barriers, landscape abutments or anti-noise systems, deposits)Protection of main embankment Deposit

Infiltrations

Infiltrations

Fossé longitudinal (assainissement de la plateforme)

Longitudinal ditch (platform drainage)

Remblai principal

Main embankment

Assurer le drainage au contact depot-remblai

Provide drainage at deposit-embankment contact

Géotextiles anticontaminants

Anticontaminant geotextiles

Tapis drainant

Drainage blanket

Drain longitudinal

Longitudinal drain


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C.7 – Embankments & fills with extra-dry materials C.7.1 - Area concerned The use of extra-dry soils (ts) envisaged by the GTR Technical Guide to Embankments & Fills involves specific stipulations, and so this issue concerns all road embankments/fills.

C.7.2 - Reference documents • Creation of embankments/fills and capping layers (GTR Technical Guide to Embankments & Fills) [10]; • Low water-content compaction of road materials and soils [57].

C.7.3 - Issues involved The construction of embankments/fills with extra-dry materials creates the following problems: • compaction difficulties in the case of water-sensitive materials. This entails a considerable void ratio, and therefore substantial permeability. Water flows cause substantial losses of cohesion in intergranular contact lines, and thus settlement in the long term with fissures and structural damage in the embankment; • trafficability problems for certain “clean” sandy materials (especially if they are homometric). The GTR Technical Guide to Embankments & Fills limits the utilization of extra-dry materials exclusively to embankments/fills < 10 meters.

C.7.4 – The materials concerned In accordance with the GTR Technical Guide to Embankments & Fills, “extra-dry” (ts) water-sensitive materials are: A, B2, B4, B5, B6 + Ci (A and B). “Clean” sandy materials with low water content are: D1, D2, B1 and B3.

C.7.5 - Solution envisaged In relation to water-sensitive materials, the GTR Technical Guide to Embankments & Fills envisages the possibility of using certain “extra-dry” materials: • in certain cases after mass humidification for materials B2, B4, C1 (B2, B4), C2 (B2, B4). • after a specific humidification study (experimental section), A1, B5, B6, C1A1, C1B5 and C2 (A1, B5). With the exception of very shaley materials which will require extensive lab studies and testing, the conditions for implementation must be examined with reference to the following solutions:

Changing the moisture condition This operation is quite delicate, since we are dealing with shaley materials with low permeability ratings. Improved fragmentation of the material (using a pulvimixer or tamping roller, for instance) and a number of humidification processes may help change the moisture condition.


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Increasing compaction energy A test section should define compaction methods (thicknesses of the layers, material implemented, number of passes, etc.) to reach quality q4 in the GTR Technical Guide to Embankments & Fills. Fragmentation of the material by different types of machinery may also be envisaged for the materials with the highest shale content(fig. 24). • for these extra-dray materials, particular attention ought to be paid to the fact that the upper section, especially in the case of less shaley materials, may not be properly compacted, although the capping layer has the proper density. Low density of this upper section may be rectified by compacting the upper layer. Likewise, surface sprinkling during compaction could improve the compacting of this surface layer (fig. 25); • the compaction quality of these materials may be appraised by a double probe test or by using other means to measure the density of the capping layer; • the technical aspects and costs of the various solutions may be of great importance. Economic calculations will be decisive as to whether these materials are reused or deposited. To solve trafficability problems of “clean” sandy materials with a low water content, we can: • sprinkle the materials, or carry out hydraulic compaction (if there are sufficient quantities of water available); • use particle size distribution correctors in the general bulk or on the surface only.

Fig. 24

Fig. 25

Fig. 24 Energie 2>> Energie 1 Energy 2 >> Energy 1 Teneur en eau Water content Variation de la densité dèche avec la teneur en eau et Variation in dry density with water content and l’énergie de compactage compaction energy Fig. 25 Sommet de la couche compactée Peak of compacted layer Compactage à WOPN Compaction at WOPN Compactage à faible Wn avec une énergie (et une Compaction at low Wn with energy >> (and a different épaisseur de couche différente). layer thickness) Fond de la couche Bottom of layer Collection « Les outils” – Sétra

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Schéma de principe de distribution de la densité sèche en fonction de la profondeur


Diagram showing distribution of dry density depending on depth

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C.8 – Embankments/fills on slopes

C.8.1 - Area concerned (1)

• Embankment and cut/embankment mix on natural ground with a crossfall of > 15% ; • Enlargement of an existing embankment.

C.8.2 - Reference documents Creation of embankments/fills and capping layers - Section 2 (GTR Technical Guide to Embankments & Fills) [10].

C.8.3 - Issues involved Construction of an embankment, or a cut/embankment, or an extension on a natural slope with a crossfall, will require proper knowledge of the geology of the site, of the soils making up the natural ground, and the site context (presence of fossil slippage, hydraulic conditions in the block, potential seismic activity, etc.). Preliminary examination and verification of the stability of an earth structure are essential for definition of the strengthening or reinforcement measures, should these be required. Certain favorable configurations do not require any particular conditions, although others involve stringent requirements to ensure stability (nailing, drainage, anchorage, surface protection, support, etc.). In addition to these specific studies, for which the required methodologies to be used are described in the technical literature (bibliography, analysis of aerial photos, geophysics, bores, piezometric characteristics, characterization of soils and interfaces, etc.), construction stipulations for the embankment to be constructed must be observed to ensure proper adhesion of the structure to its immediate surroundings. The recommendations below concern this point exclusively. Extensions to an existing embankment in order to create extra routes or to combat erosion of slopes will also require proper anchoring of the unit to be built over the existing structure.

C.8.4 – Recommended solutions Creation of keyways over a sufficient width (at least 4 meters for embankments/fills on a slope, and at least 1 meter for extensions) to anchor the structure to a sufficient depth in the bearing soil or the support embankment, and allow proper implementation of the embankments/fills. A crossfall in the keyways towards the interior of the block is advisable to prevent runoffs from one keyway to another, and improve compaction at the sides of the embankment (a gradient of 10% is often advocated). To prevent the water from stagnating, the gutter unit must have a sufficient descending gradient (5% or more, depending on the granularity of the materials), and evacuation on the lower section must be implemented and maintained for the entire lifespan of the structure (if these conditions cannot be guaranteed, the slope of the keyways could be oriented towards the exterior of the structure). To improve adhesion, an anchoring spud can be placed at the foot of the embankment as a buttress. This may not be necessary in the case of embankment extensions.


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C.8.5 – Construction stipulations (1) Stripping of the topsoil or of the bottom course to produce a healthy bearing soil layer. (2) To create the anchoring spud, the cuts will be removed and substituted by a quality material to a depth of one meter. In certain cases, depending on the results of the stability study (this is performed if the bearing soils show any risk of instability), the spud could have an extended width at the foot of the embankment. (3) The keyways are built as the embankment progresses, by executing a recess in the natural ground, at a height at least equal to 1.00 meter (0.50 meter in the case of extensions). (4) The bottom section of each keyway will be compacted as in the case of the base of the embankment. (5) The materials extracted from the keyways will be considered cut materials. If they are not reusable, they must be removed – if they are reusable, the utilization conditions advocated in the GTR Technical Guide to Embankments & Fills for construction of the embankment must be observed. (6) If water ingresses are observed during construction of the keyways, drainage facilities must be added to them (figure 26). Construction stipulations for extensions Only stipulations (1), (3) and (4) are compulsory. The anchoring spud (2) need only be added in the case of extensions to embankments/fills on sloping ground, and reutilization of the material extracted from the keyways (5) may only be envisaged for large extensions (> 3 meters). It will be observed that, before and during work, it will be necessary to ensure continuity in the functioning of the drainage systems relating to the existing structure (figure 27).

C.8.6 - Observations In certain cases where the natural ground has a considerable descending gradients, this methodology may be applied in accordance with the nature of the embankments/fills, the bearing soils and their hydrogeological environment, presence of other structures, etc. The remarks in section 2 recommend special remuneration for the keyways (by the square meter or linear meter if the geometry is well defined); in the case of small quantities, however, this task could be remunerated in terms of cut and embankment prices. xxx

Fig. 26 (Excess fill)

Fig. 27 (Excess fill)


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C.9 – Cuts/embankments/fills on a waste dump or a polluted site C.9.1 - Area concerned Where the work crosses a dumping site, whether or not it is an authorized site, on a cut or an embankment. Embankment or a cut in a polluted area.

C.9.2 - Reference documents • Directive 75/442/CEE, modified by directives 91/156/CEE and 36/350/CEE, in relation to disposal of waste [34]; • Outline law of 15 July 1975, modified by the law of 13 July 1992 governing the limitation of storage of waste in reserve as of 1 July 2002 to end waste only. Decree No. 97-517 of 15 May 1997 governing the classification of hazardous waste [30] [31]; • Notice in the Official Journal of 11 November 1997 in relation to the new European nomenclature of waste [53]; •

Decree No. 98-679 of 30 July 1998 concerning road transportation of waste [42];

• Soil improvement by vertical rigid inclusions – Application to construction of embankments/fills on mediocre soils [64].

C.9.3 - Issues involved It is not infrequent for road alignments to encounter dump sites, whether or not they are authorized or controlled. Work on these sites, whether they are part of cuts or embankments/fills, requires the implementation of special earthworks techniques, in view of the extremely heterogeneous and changing nature of the waste on site. In particular, the construction stipulations adopted must ensure general stability of the structure, sufficient bearing capacity in the subformation, and proper administration of settlements in the short and long term. Moreover, depending on the toxicity of the materials encountered, a specific study must be performed on the treatment of runoff water, recovery of waste dump leachate, treatment of gases, etc., and hence the importance of the results of chemical analyses which can condition the data on a project: • setting the longitudinal section; • whether or not to maintain all or part of the waste dump? • choice of the isolation and drainage systems, if required (use of geomembrane waterproofing systems [DEG]). In the absence of geometric constraints, planners will focus their choice in accordance with volumes, and will prefer an embankment trajectory rather than a cut crossing necessitating unavoidable “displacement” of a volume of waste for which the administrative and financial conditions in relation to extraction, transportation and deposit will always create considerable constraints. Compulsory points along an alignment and a high level of waste dump pollution will leave planners little room for maneuver, and they will be forced to define cutting earthworks, or consider a purge followed by substitution, or both these operations simultaneously, if both conditions are true for the same site. As of the outset of the studies, or before, it is highly advisable to inform the specialist Prefectoral services in charge of application of decrees of the existence of the project, and to ask their opinion.

C.9.4 – Preliminary tests and investigation work In due consideration of considerable extra costs arising from work over a waste dump area, precise quantitative and qualitative information on the site must be forthcoming. Investigation and delimitation (surface area, volume) of the deposit zone: • investigations using existing documents, plans of quarries, cartography (chronological comparison), air cover, etc.; • density and implementation of bores as a result; • sample borings using shovels, auger drills, and geophysics equipment; • samples from reworked intact terrain for geotechnical tests and chemical analyses in labs; Collection « Les outils” – Sétra

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• establishment of maps and/or serialized sections, depending on the nature of the soils encountered and the results of lab analyses; • nature and characteristics of subsoil, presence of water (samplings, piezometric reports); • chemical analyses to classify the site by sectors as waste dump class 1, 2 or 3; • leaching of sample waste taken from different depths, analysis of waste dump leachates. In both cases, research work into: • pH; • conductivity (in m); • chemical oxygen demand (DCO); • heavy metals (iron, nickel, cadmium, zinc, lead, chrome, etc.); In situ testing of the mechanical behavior of layers: • penetrometer; • pressure meter; • recordings of drilling parameters; etc. In addition to issues involved in the re-use of natural and stable treated materials, the section of the study concerning pollution should lead to a distribution diagram for deposit earth to centers for classes 1, 2 and 3, as per the chemical values obtained for the samples, in comparison to the values of the permitted thresholds set in regulations (method for performance of analyses on which the threshold values are based – leaching product or raw product). Analyses of checks must be envisaged during construction work on the site.

C.9.5 – Recommended solutions - implementation In the treatment of waste dumps Three large categories of solutions may be considered:

Removal of materials This solution consists of substituting all waste intercepted by a filler material or material from cuts. This often carries heavy costs, particularly in view of the constraints in relation to regulations, extraction, transportation and deposit. Possible environmental nuisances must also be taken into consideration (smells, psychological impact, etc.). The volume to be removed must take account of a certain thickness of polluted soils underneath the waste dump material.

Dynamic compaction This method consists of a free fall from around twenty or thirty meters of a pylon with a Newton mass of hundreds of kilos. The dynamic consolidation technique reduces the materials' void rating by violent energy compaction. The first applications of dynamic compaction in the stabilization of “industrial waste dump” or “household waste deposits” embankments/fills were presented in 1979. The thicknesses generally treated with normal levels of energy are around 8 – 10 meters. Repeated experience has shown that this type of treatment is particularly suitable. It is extremely efficient in terms of the nature of the masses of refuse deposits (heterogeneity, thickness, age and mechanical behavior). The geotechnical feasibility study must set out the precise nature of the refuse deposits. The pressure meter test is a good tool for appraisal of mechanical characteristics prior to treatment, and also a good way of checking the effectiveness of treatment. The static penetrometer is also used to classify waste dump deposits. From the environmental point of view, the measurement of vibrations conducted to date shows that compaction energy is generally rapidly absorbed by the refuse deposit, which is usually quite compressible. Preliminary vibration measurements will verify this point, particularly in relation to the presence of a water table or continuous blocks. Collection « Les outils” – Sétra

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Rigid inclusions The principle consists of creating a network of concrete columns (inclusion), which moves across and “reinforces” the compressible layers up to the resistant soil. Above this, forming a slab, a gravel or cement-treated soil distribution mattress forms for transfer of the loads induced (embankments/fills, traffic, etc.) towards the inclusions and good soil. This reinforcement technique is particularly suitable for working over putrescible soils at a considerable height (> 6 meters). Specific studies determine the mesh of the network of columns, their diameters, their consistency (reinforced or non-reinforced concrete), and also the thickness of the distribution mattress. The inclusions may be created using a number of methods (vibratory driving, vibratory tube hammering, auger drill driving, etc.). They may require pre-drilling if “hard horizons” have to be negotiated to prevent situations where piles cannot be driven to the required level.

In the treatment of polluted sites There are four ways of addressing the problem:

Systematic excavation and evacuation at an approved treatment center As for the treatment of waste dumps, this solution consists of exhausting purging of polluted earth and removal to an approved treatment center (technical landfill center class 1, bio-center, incinerator, etc.). It is costly and difficult to manage in view of the uncertainties across the polluted area. The main constraints with respect to regulations are as follows: • transport in observance of ADR regulations (European agreement concerning international road transportation of hazardous goods) in relation to waste transportation; • Prefectoral declaration by the transporter for transportation of waste; • establishment of a prior acceptance certificate (CAP) by the center receiving the polluted earth; the earth must be compatible with the technical specifications attached with the Prefectoral order authorizing the center to carry out is activities; • establishment of a monitoring schedule for industrial waste (BSDI) for each consignment. The main advantage of this method is its rapid implementation, which depends only on the rate of excavation and the capacity of the center to accept the polluted products and earth.

Excavation, sorting and selective evacuation at approved treatment centers The approach of this solution is similar to the previous solution. Sorting, however, especially if it is carried out painstakingly, can substantially reduce costs by removing polluted earth to proper processing units. A qualified technician is required on site, as is analytic equipment for rapid determination of the choice of the processing unit. This technique requires the organization of secure areas for provision storage and sorting. The constraints with respect to regulations are as for systematic evacuation, although these do not apply for the evacuation or reutilization of materials considered as inert waste.

Treatment in situ with no excavation This solution is the best from the environmental and financial viewpoints - it consists of treatment of polluted earth in situ with no excavation. The pollutants are either removed from the soil or degraded as metabolites which do not harm the environment. In situ methods require extremely detailed investigation of the terrain, especially the contours of pollution, so that no polluted soil is left behind to repollute the depolluted zone. Attention must also be paid to monitoring of treatment, focusing on the evolution of the concentrations and metabolites produced. For example: • air-slaked lime treatment of soils contaminated by heavy metals, hydrocarbons or organic substances; • biological treatment of earth contaminated by aliphatic hydrocarbons; Collection « Les outils” – Sétra

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• • • •

venting of earth contaminated by volatile halogen components; treatment by electrodeposition and/or migration of heavy metals; electrical treatment for organic pollutants (oxidation-reduction); stripping of chlorine solvents.

This type of treatment requires preliminary in-depth investigation, and the possibility of freezing over the polluted area during treatment for a period of a few weeks to several months, or 1 – 3 years for extremely complex cases of pollution. Certain kinds of treatment (electrical treatment, for instance) may be implemented and operate in a transparent and compatible fashion with normal site usage.

Excavation, sorting and treatment on the site After selective sorting of polluted earth and temporary storage, this solution consists of implementing a decontamination technique adapted to the pollutant. In addition to those already mentioned in the “in situ” treatment section, we may add the following techniques: • heat treatment by a mobile heat desorption or incineration unit; • earth scrubbing unit. Depending on their scope, these facilities may be subject to regulations for classified facilities. The advantage of these techniques is that they substantially reduce environmental nuisance and costs by elimination of transportation and rapid action on the contaminated area. They do, however, require sufficient land requirements for installation of the storage and treatment areas. This solution constitutes a good compromise between evacuation and in situ treatment. Caution is, however, of the essence so as not to cause any environmental damage (noise, smells, etc.) to the surrounding area.

Confinement of materials This solution leaves the polluted earth in place and provides a barrier which prevents pollutants from migrating. It implements techniques commonly used in public works: • membrane walls; • extra-thin walls ; • diaphragm walls; • sheet piles; • implementation of membranes; • grout injections. These techniques require the use of a monitoring system to run a continual check on the efficiency of the structure over its entire lifespan. It is a method which does not treat the pollution, but simply provides safety on site. It is used when no other methods are technically or financially viable.

Instrumentation and monitoring In the case of waste dumps, since the main problem relates to the risk of settlement, instrumentation must serve to quantify general movements in the structure, especially: • measurements of soil settlements using gauges associated with topographic surveys; • monitoring of trends in interstitial pressures in the soil via sensors; • checks on lateral deformations in soils using inclinometric tubes. Use of this instrumentation must observe a precise implementation in accordance with soil stresses validated by a geotechnician.

Pathology In the case of waste dumps, the pathologies observed are those normally found in compressible soils. They are most often linked to secondary settlements which have been poorly managed, of mechanical and/or chemical origin. Collection « Les outils” – Sétra

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C.10 – Cuts in aquiferous zones C.10.1 – Structure concerned Road cut across an aquifer. Cuts for the construction of a retaining wall, cuts for drainage structures and work in maritime areas are not covered in this section.


Special Bulletin V, Public Works Research Laboratories, “Hydraulics of soils.” [55];

• Special Bulletin III, Public Works Research Laboratories, “Stability of slopes ” 2 volumes [54]; 1 – Natural slopes 2 – Cuts and embankments/fills •


•

Article No. 10, Water Act No. 92-3 of 3 January 1992 and decree of 29/03/1993 [52].

C.10.3 - Issues involved In the presence of an aquifer identified by a geotechnical study, it is not always possible to deal with the longitudinal section in such a way as to escape the difficulties and costs of reinforcement work for a number of reasons, be they technical, such as the trajectory along compulsory points on the alignment, or environmental, such as an obligatory entrenchment (noise, views, atmospheric pollution in suburban areas). Water in an aquifer plays a harmful and extensive role in relation to the contents of slopes and road platforms. Hydraulic studies of soils show that there are three types of water: • bound water – retained by capillarity around grains, co-existing with the vapor zone (air); • capillary fringe water - this is water which is suspended and non-mobile, situated between the other two types. It occupies all gaps within the soil (water-saturated soil), and the height it reaches depends on the nature of the soil and the atmospheric conditions if the water table is close to the surface; • a water table’s free water flows between the interstice of a soil or the cracks in a rock, and its general behavior pattern is gravitational (influence of gravity). Of these three types, it is the third which causes most problems for earthwork contractors, when the longitudinal section intercepts aquifers. The project designer must draw up construction stipulations on the basis of the geotechnical studies which ensure both the stability of slopes in the cut and the bearing capacity of the platforms. The ”earthwork” methods often converge around drainage and lowering of the water table, occasionally around membrane walls (cuvelage – an underground waterproof lining), or mixed solutions when the main concern is protection of the environment (figures 28 and 29).

Figure 28


Figure 29

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Figure 28 Sol Formation perméable Formation imperméable

Surface of ground Permeable formation Impermeable formation

a) nappe libre

a) Free water table

Piézomètre Terrain non saturé Zone saturée : frange capillaire Surface piézomètrique ou surface de la nappe La nappe Le mur

Piezometer Unsaturated ground Saturated area: capillary fringe Piezometric surface or water table surface The water table The wall

Figure 29 Formation imperméable Formation perméable Formation imperméable

Impermeable formation Permeable formation Impermeable formation

b) nappe captive

b) Captive water table

Surface piézomètrique Le toit La nappe Le mur

Piezometric surface The roof The water table The wall

Définition des nappes

Definition of water tables

Water in soils where earthworks are to be carried out causes three types of problems: 1) an increase in timelines due to observance of administrative procedures in connection with the Water Act; 2) drainage work during the preparatory stage which may take several months, often due to the slowness in lowering the water table and special earthwork phasing to reduce the moisture condition of cut material beneath the water table and to minimize problems concerning the reutilization of soils. Particular attention will be paid to the drainage of water with a high content of salts; 3/ adaptation of methods of execution to solve problems: • trafficability during the execution stage beneath the water table; • platform bearing capacity and earthworks slope stability in the short and medium term; • reutilization of the soils removed (temporary deposit, treatment, etc.); • choice and sizing of drainage to ensure the long-term bearing capacity of the subformations and stability of the slopes.

C.10.4 – Studies to be carried out The objective of the studies is to set out the problems posed by water, and to provide information on the water tables. A number of simultaneous or successive studies must be conducted: • a geological study including a visit to the site, and on-site preliminary surveys to specify the nature of flows and locate the aquifer levels; • a hydrogeological study for investigation of the water tables (levels, directions of flow, sources, catchment areas, expanding areas of moisture, tapping of water tables, protected areas, dewatered soils, etc.); • a geotechnical study to investigate the nature of soils, intrinsic characteristics (C and φ), permeability of soils via in situ large-scale tests in due consideration of anisotropy of soils and rocks (cracking, diaclases) and smaller-scale lab measurements of samples). Specific studies such as: • slope stability with the assistance of calculation software for justification and sizing of the stipulations for construction and reinforcement, if this is required; • sizing of the platforms in accordance with the classes concerned; Collection « Les outils” – Sétra

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• hydraulic impact study on the effect of lowering the water table on the environment and on surrounding structures. Although they are connected, the means used to bring down a water table sufficiently beneath the level of the subformation from slopes are occasionally different depending on whether the procedure focuses on the short or long term: the use of drive point lines or dewatering wells are assigned to short periods on site, while drainage trenches and blocks to take over this function are devices to be used at the final stages to ensure stability through gravitational water flow towards an outlet. The water outlets in the natural surroundings ought to be staked out from the earliest stages of the project. Large structures, complex hydrogeological contexts and environmental sensitivity are also factors which can lead to soil hydraulics studies in advance of the actual project, perhaps with the assistance of mathematical models to evaluate the reciprocal environment/road alignment impacts.


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C.10.5 – Recommended solutions Work on cuts around a water table will necessarily involve work to lower the table (drainage) and/or work to isolate (impermeabilize) the structures. For earthworks sufficiently close to a confined body of water, a study must be made of conditions which will not raise the “impermeable” section of soil left in place above the aquifer (roof of the aquifer). If the conditions are not verified, ways of reducing interstitial pressures will have to be envisaged by lowering the piezometric surface (discharge trenches and shafts). The most commonly used methods are set out in the tables below: In the case of cuts in loose materials with low permeability ratings: Issues involved Objective Constructio n works stage

Type of aquifer

Execution of cut

Gravitational

Lowering ditch

Capillary rise

Anti-capillary barrier

Short term Constructio n works stage

Trafficability

Slope stability

Bearing capacity of subformation

Maintaining a slope on a treated track / connected with longitudinal ditches

Drainage trench before cut

Purge or substitution

Track in granular material

Slope adapted to materials

Treatment purge

Drainage shield Drainage trench Reinforcement of slope (subhorizontal drains - vertical nailing) Drainage trenches

Drainage blanket - drains

Short term

Operational stage

Gravitational

Not applicable

Not applicable

Long term

In the case of cuts in materials with medium to high permeability ratings: Issues involved Objective

Type of aquifer

Construction works stage Gravitational Short term

Operational stage

Execution of cut

Trafficability

Dewatering wells Drainage wells Drive points Membrane walls (except rocky media)

Maintaining a longitudinal slope Longitudinal ditch in advance

Not applicable

Not applicable

Long term


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Slope stability

Bearing capacity of subformation

Drainage wells Drainage trench Drive points Possible substitution Dewatering wells by drainage network (evacuation of water) Reinforcement of slope with: Nailing for rocky block Drainage shields or trenches for incoherent soils

Possibility of treatment with hydraulic binders, subject to sufficient lowering

March 2007


In a lowering situation, these solutions must be examined within the context of the Water Act (article 10). The diagrams and photos below show examples of the possibilities mentioned above.

Figure 30: Trenches or drains on a platform

Figure 31: Strengthening an earthworks slope by drainage

Water table flow 1 Drains disposé en chevrons avec collecte des eaux latérales 2 Drains transversaux avec collecte dans un drain longitudinal central 3 Trench drains with collection in a unilateral drain (sporadic outcrop of water table) 2 Drains transversaux avec collecte dans un drain longitudinal central Principe de stabilisation […]


1 Herringbone drain layout with lateral water collection 2 Cross-wise drains with collection in a central longitudinal drain 3 Trench drains with collection in a unilateral drain (sporadic outcrop of water table) 2 Cross-wise drains with collection in a central longitudinal drain Principle of stabilization of slope intersecting a water table with drainage trenches (discontinuous drainage wall)

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Instability in a cut slope due to the presence of a water table.


Side view of instability in the same slope.

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C.10.6 - Observations The geosynthetic features of geospacers and geodrains can make an effective contribution to the solutions proposed, either as additional features or to replace granular materials. The solution of driving piles into a slope, perhaps with a plinth wall and subhorizontal drains (whether bored or not) is often used to deal with a large mass displaced by a creep phenomenon. In the case of drainage networks, a monitoring and maintenance strategy must be implemented on the facility by those in charge of the project – this involves measurement of the various flows and possibly a piezometric unit when there is a risk of damage to the environment. A sliding slope which has disorganized the slope overall means it has to be rebuilt over the entire damaged land requirement, with an internal drainage system.

Construction of a drainage trench to lower the water table using drive points (not visible above – on the left).

Capping layer structured as loose stones to prescreen the water table Line of drive points used prior to the cut. over the land requirement.

C.11 – Embankments & fills in aquiferous zones C.11.1 – Structures concerned Embankment in a area liable to flooding (a). Embankment of height < 1 m with suboutcrop water table (b). Embankment of which part of the thickness is built in water (c).


Regulation NF P 11-300 - Classification of materials [45];

•



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• Recommendations for the use of geotextiles (French Geotextiles and Geomembrane Committee, CFGG); •

Study and construction of embankments/fills on compressible soils [8].

C.11.3 - Issues involved The main difficulties encountered are as follows: • influence of capillary rise in the main body of the embankment (depending on the nature of the materials and the size of the structure) (structure type a, b, c); • use of materials on soil with a low bearing capacity (b and possibly a); • use of materials in water (c); • wake wave erosion of earthworks slopes (a, c); • rapid recession instability (a, c). Hydraulic transparency with regard to flooding is effected by specific stipulations (discharge structure) set out in a hydraulic study. The design of the embankment will not seek to guarantee this transparency, although it will contribute to it. Compressible embankment bearing soils are frequently found in aquiferous (water bearing) zones.

C.11.4 - Studies On the basis of a geological, geotechnical and hydrogeological study of the site, design studies for the project will concern the following areas: • compressibility of the soils; • underground hydraulics; • general stability of the embankment; • constitution of the embankments/fills (type of material, implementation).

C.11.5 – Recommended solutions 1) Blockage of capillary rise The techniques to be implemented depend on the influence of capillary rise on the materials in the structure and the dimensions of the structure with respect to the risks of: • reduced bearing capacity of the upper part of the earthworks; • general stability of the embankment. The easiest solution is to build the embankments/fills using materials which are not water-sensitive, up to the highest water level (PHE) + 0.5 meters after settlement. This solution involves using the finest quality materials. There are solutions which allow normal cuts to be reused. Treatment of soils (using lime or lime with hydraulic binders) restricts capillary rise and improves the mechanical characteristics. This level of soil must be fully compacted, and implemented with extra thickness or a layer of gravely material laid initially as an anvil. In situ treatment of the bearing soil may also be considered.

2) Low bearing capacity embankment bearing soil: risk of Ø on the upper section of the earthworks [PST] or Ø on the subformation level [AR], due to fluctuation in the water table In the case of lower embankments/fills A substitution must be made in such a way that the main body of the embankment has a thickness of at least 1 1.5 meter of non-water sensitive materials (possibly with an intermediate geotextile layer).

Embankment in a area liable to flooding Here it is occasionally necessary to substitute the soil in place. Removing the topsoil, however, can lead to trafficability problems and difficulties of execution. In the case of embankments/fills of a height over 2 meters, it is therefore often advisable to preserve it and implement a thick layer of non-water sensitive materials (possibly with an intermediate geotextile layer). Collection « Les outils” – Sétra

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3) Implementation of materials in water In this case, only the use of non-water sensitive and non-degradable materials is recommended. The use of rounded materials will constitute the best method, since this is the best implementation without compacting, and compaction carried out on the waterless surface will be effective at a greater depth. In the case of embankments/fills in water to a thickness of 2 meters, compaction on the surface using classic methods is insufficient. Other techniques must be considered, such as dynamic compaction or vibroflotation. Another solution consists of associating the layers from the bottom up: riprap, separation geotextile (with sufficient penetration hardness).

4) Wake wave slope erosion In flood situations, wake waves can produce erosion in earthworks slopes. Here the design of embankments/fills must include protection of the slope surface up to the highest water level, using one of the following solutions: • geotextiles and replanting or geomembrane; • riprap; • treatment of soils with hydraulic binders on the slope facing.

5) Rapid recession instability In general, the structures concerned are located in sites with slow recession. In the case of embankments/fills implemented in proximity to torrential water courses (rapid recession), the immersed section must consist of materials with a high permeability rating - possibly non-water sensitive gravely materials. The use of fine treated soils ought to be examined. This solution could envisage an embankment with recharge on the slope of gravely materials and perhaps riprap, or a low abutment, the thickness of which would be justified by general stability calculations. Particular attention will be paid to dissymmetric recessions, although the hydraulic study generally helps envisage sufficient discharge structures.


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C.12 – Underground cavities C.12.1 - Area concerned Sites with known or potential underground cavities, the evolution of which could affect the structure. The cavities may be natural or man-made.


Plans for Prevention of Natural Risks – General guide [60];

•

Plans for Prevention of Natural Risks – Risks of earth movements – Methodological Guide [61];

•

Risk Exposure Plans

•

Applied geophysics: Code of Good Practices [58];

•

Guide to Cavities – INERIS / DPPR / LCPC (provisional document pending validation).

•

Natural Risks – Liaison Bulletin, Public Works Research Laboratories No. 150 - 151 [56];

• Abandoned underground quarries. Risks and prevention. Seminar at Nainville-les-Roches (1993). International Engineering Geology Association (April 1995) •

Detection of underground cavities using geophysical methods – Practical Guide [].

C.12.3 - Issues involved Characterization of uncertainties (nature, size, depth, density etc,), of possible knowledge on the subject, and the risk of occurrence. Characterization of the effects of uncertainties. The nature and extent of possible structural damage to the site must be specified. Estimation of the probability of occurrence of this type of damage.

C.12.4 – Studies to be carried out Type of study

Classes

Meteorological situations

Preliminary geological analysis ................................. EP**

Yes

Yes

Oral proximity study ......................................................EP

Yes

Yes

Research in archives (old documents, specific surveys, maps ...) .........................................................................EP

Yes

Yes

Research of indices photo-interpretation: aerial ........................................... AP infrared ....................................... AP - visit to site ...................................................... EP and AP - geophysics .................................................................. AP - monitoring of stripping ............................................... AP

Yes if adapted Yes if adapted Not always necessary

Yes if adapted Yes if adapted Yes

Investigation - specific stripping................................................AP and P - shovel sampling .................................................AP and P - destructive boring: (tricone, bit).........................AP and P - ”geological” bores (auger drill) ...................................... P - visit to cavities (human, camera).................................... P - estimation of shapes and volumes .................................. P

/ Yes Yes Yes (Yes)* (Yes)*

Yes Yes Yes / (Yes)* Yes

*if technically possible **level of studies: EP preliminary study - AP preliminary project study - P project study


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In the case of structures on cuts, studies may be accompanied by investigation at the bottom of the cut (better detection and/or lower costs if the covering of the cavity is smaller), or during work in accordance with the anomalies encountered (cavities, sand pockets, access shafts, etc.).

C.12.5 - Recommended solutions Choice of the methodology to protect the structure will depend first and foremost on characterization of uncertainties, and the outcome of preliminary studies, depending on whether or not it was possible to survey and characterize the cavity. In general, man-made cavities are finished unstable voids. Thus it will be necessary to find them and usually make a choice between filling them in or reinforcing them. Natural cavities (karstic network) often consist of unfinished voids, and in this case the most common concern is to prevent their development or limit their effects. The best solution for a cavity problem will be that which provides the best “risk reduction / costs of investigation and treatment” ratio. For example, on a given site, if the risk involves minor subsidence (diameter less than 2 meters), the best solution could be implementation of continuous geosynthetic protection with no detailed study of the area concerned.


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Solutions

Characteristics

Area of application and restrictions on use

Checking and monitoring

Reinforcement

Consolidation of existing pillars. Addition of pillars. Rock bolting of the roofs.

Known accessible cavities.

Possible instrumentation. Maintenance of accesses for regular monitoring during the operational stage.

Filling from the inside

Mechanical filling with sandy material.

Known accessible cavities. Geometry adapted.

Characteristics of the material. Checking of pressing and/or compaction.

Filling from the outside

Solid or liquid injection for a hydraulic system. Hydraulic filling with sand.

Known cavities. Preliminary estimation of volumes. Geometry adapted. Creation of air vents on higher sections.

Characteristics of the product injected. Drive back at the air vents.

Caving

Removing the empty space by collapsing the cavity.

Known deep cavities. Require consolidation of collapsed soils.

Verification of the effectiveness of caving and non-disturbance of the water table system (preliminary analysis and additional investigation afterwards, etc.).

Dynamic tamping

Removing the empty space by collapsing the cavity.

Known or unknown suboutcrop cavities.

Monitoring of mesh and results (preliminary analysis and subsequent testing).

Impermeabilization of ditches and retention tanks

Preventing the migration of surface water to karstic ducts.

Unknown cavities with a risk of bringing in fine materials.

Watertightness of the systems and subsequent monitoring.

Continuous geosynthetic reinforcement

Preventive solution to guard against serious accident (creating a surface depression in case of collapse).

Unknown cavities or subsidence φ < 4 meters. Sizing study.

Verification of system continuity and implementation and subsequent monitoring.

Soil reinforcement using bars, reinforced concrete slabs ...

Preventive solution.

Small known cavities (1 - 5 meters). Sizing study.

Checking of products and their implementation. Subsequent monitoring.

Expanding embankments/fills Method currently undergoing study and experimentation

Implementation of sufficient thickness to create a selfsupporting vault.

Profile on embankment. Sizing study.

Choice and compaction of materials. Instrumentation and monitoring.

Deepening cuts

Leveling of earthworks to beneath the cavities.

Profile on cut. Known or unknown cavities.

Monitoring of work and observation of voids encountered during earthworks.


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D – Constructional measures (case studies)


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Case study No. 1 Treatment of visibility problems and use of surpluses

Characteristics of the project

- Open motorway 16 km long with surplus at outline preliminary project/design stage [APS] of 1,500,000 m3 (built in 1998). - Type of soil: altered hard shale class R34 / GTR Technical Guide to Embankments & Fills.

Stage of study

Project report drawn up with residents.


- Village in hollow in valley – residents’ view of motorway. - View of Normandy bocage pasture landscape for users.

Problem

- Residents 400 m from the motorway and 55 m below did not want to see the motorway, and less so after the land reallocation. - In due consideration of the quality of the view of the Normandy bocage landscape on the horizon observed by users, this view should be kept at a distance. - Research into reduction of surplus was not the origin of procedures.

Solution used

Construction of a light earth mound barrier and therefore an extension to the platform satisfied the desires of residents as far as possible (the top sections of trucks were still visible), while maintaining the views in the distance for users. This construction stipulation used up surplus materials. The absence of any surplus material would have led to construction of the earth mound barrier in any case.

Diagram

Advantages

- Elimination and reduction of visual impact - Reconstitution of a bocage system at the road edge - Utilization of surplus material - No safety rail - Guttering in water channel - Easier maintenance

Disadvantages

Larger land requirement

Reference

Autoroute des Estuaires A 84 - Section Coulvain - Guilberville

Ligne de vue sur la vallée Ligne de vue des riverains

Line of vision over the valley Line of vision for local residents

TN

Natural ground

Schiste dur au ripper Talus non végétalisé

Hard shale cut with ripper Unplanted slope


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Case study No. 2 Excess materials / Landscape


Free motorway, 20 km with an excess at project stage of 3,000,000 m3 of silty soils.


Motorway in open country on a slightly undulating site in bocage pasture landscape with isolated farmhouses. The parcel mainly features permanent meadows surrounded by bocage hedges.

Problem

The project was a full cut to satisfy all residents and municipalities, and generated 3,000,000 m3 in excess material to be removed from the land requirement.

Solution used

As a base solution to the tender documents [DCE], transport of materials at a quarry to be redeveloped was considered costly. The decision was taken to authorize “contractor” variants. An impact study report was drawn up in conjunction with the DIREN and attached with the DCE. This set the “game rules”; forbidden areas, the landscaping models to be respected, hedgerows to be retained, water flows, etc. Observation of these rules formed part of the judgment criteria for tenders, which had to be approved by the DIREN before they could be accepted. Therefore the contractor suggested raising a number of agricultural parcels next to the motorway, which were in hollows or were downhill from the landscaped mound barriers or from district road restoration embankments/fills.

Diagram

Advantages

- Elimination of excess materials on parcels adjacent to the motorway, preferably in proximity of overpasses for restoration of embankment routes. - Landscape integration of the motorway, earth mound barriers for noise protection, and embankment restoration routes for overpasses. - Better accessibility for areas around the old barriers formerly planned. - Limitation of land requirements in the absence of plantations. - Lower cost than transport, and final depositing in accordance with the law on waste. - The contractor handled all problems with residents.

Disadvantages

- Solution dependent on the goodwill of residents, particularly in terms of indemnities, which were negotiated by the contractor only after it had been awarded the contract. - Extra stripping and restoration work, entailing longer work timelines. - Work on restoration of surface flows.

Reference

A13, Bayeux Calvados diversion.

TN

Natural ground

Réhaussement des parcelles A13 Réhaussement des parcelles

Raising of parcels A13 Raising of parcels

Merlon de protection phonique

Earth mound barrier for noise protection


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Case study No. 3 Earth movement / Landscape / Hydraulics / Town planning


- Straight-alignment motorway, 4 km. - Embankment from a ”borrow cut of fluvio-glacial material” at a distance of 8 km.


- Motorway in a suburban setting, in a compressible area liable to flooding. - The Lavanchon river, partially dammed, creating frequent floods. - Narrow flat valley flanked by mountainous terrain; grandiose environment (Vercors). - Compressible soils (15 - 18 m of shale).

Problem

- Motorway placed in high embankments/fills in the overview / background summary [APS] to avoid flooding, and thus: - Difficulties in relation to serious settlement problems (project at + 4m, approximate settlement 1 m). - Many structures for hydraulic transparency and maintenance of the floodable nature of the area. - Problem of overpasses set at ≈ 10m/Tn (settlement + integration). - Problems relating to noise screens and difficult project integration.

Diagram: overview / background summary [APS] stage

Solution employed: Motorway set on natural ground. Construction of a counter-canal and recalibration of the river.

Advantages

- Reduction in terms of embankments/fills and transport - Limitation on overpass ramps - Easier integration - Noise protection ”masked” or replaced by earth mound barriers - Creation of a pedestrian/cyclist route (green flow) - Economic - Partial elimination of flooding in inhabited areas

Disadvantages

Reworking of the project (new hydraulic studies and negotiation)

Reference

A51, Grenoble Col du Fau, Municipalities of Claix, Varces, Allières & Risset

Schéma : niveau A.P.S. Ecran Zone inondable Tassement > 1 m Collection « Les outils” – Sétra

Diagram: overview / background summary [APS] stage Screen Area liable to flooding Settlement > 1 m – 146 –

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A 51 Plaine de Lavanchon Lavanchon 15 – 16 m d’argile

A 51 Lavanchon Plain Lavanchon 15 – 16 m of clay

Solution retenue :. Ecran A 51 Contre-canal Plaine de Lavanchon Lavanchon

Chosen solution Screen A 51 Side canal Lavanchon Plain Lavanchon


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Case study No. 4 Earth movement / Borrowing


Ordinary section 16 km, 7 million m3 to be dozed, of which 3.5 million m3 in embankments/fills, see drainage materials.


Suburban section, plains and mountain; grandiose context, Vercors and Grand Brion. Project altitude 300 - 900 meters.

Problem

Necessity of embankment materials (3.5 million m3), but no borrowing possible (environmental constraints, difficult political context, etc.).

Initial solution chosen in the overview / background summary [APS]: Use of external supply; considerable extra costs, not addressed; transport issues.

Solution chosen: On the basis of additional geotechnical and geological studies, adaptation of the project (red line and cross section) to find a balance for earth movement and ”transform” a cut into a borrowing. Definition of a strategy.

Advantages

Absence of borrowing (no specific administrative procedure, reduction in transport and administration of costs of materials.

Disadvantages

Variable project geometry to be administered until completion of earthworks. - Larger land requirement.

Reference

A51 Grenoble Col du Fau, Isère district, Municipality of Vif.

Chosen solution Screen A 51 Side canal Lavanchon Plain Lavanchon

Solution retenue :. Ecran A 51 Contre-canal Plaine de Lavanchon Lavanchon Solution retenue :. Coupe A - A A 51 TPC élargi Collection « Les outils” – Sétra

Chosen solution Cut A-A A 51 Widened central reservation – 148 –

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P.L. A 51 adapté


Adapted longitudinal section of A51

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Case study No. 5 Environment – Drainage


Straight-alignment motorway, crossing plains perpendicularly, length 2.5 km with full semiinterchange; longitudinal section almost horizontal.


- Flood plan flanked by high relief to the east and west. - A large dammed river (Gresse). - Plain occupied by agriculture and isolated hamlets, some of which are in close proximity to the project. - Presence of tappings of Grenoble downstream with probable direct communication via the water table. - Direct communication via the water table. - Project located in the protected area at some distance from tappings: high sensitivity.

Problem - Difficult if not impossible (on ½ interchange) to guard against pollution of the water table and the Gresse river. - Barrier-type devices (GBA) were considered in the overview / background summary [APS] with an upper barrier, height 3.50 m. Strong visual impact.

Initial solution used in the overview / background summary [APS]: Replacement of GBA + barriers with earth mound barriers on ordinary section + subhorizontal hydraulic racking system for collection and prescreening.

Advantages

- Easier project integration (earthworks slope + vegetation) - Limited plain cut effect - Reutilization of materials unsuitable for embankments/fills - Elimination of noise screens - Limited maintenance in the event of accident - Greater consideration of fauna

Disadvantages

Complex hydraulic system

References

A51 Grenoble / Col du Fau, Municipalities of Varces, Allières et Risset, Vif.


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Schéma : projet A.P.S. Rivière de la Gresse

Diagram: overview / background summary [APS] River Gresse

P.S. Passage agricole

Overpass Agricultural route

Faible pente Zone sensible / Captages P.I. Coupe A-A A 51

Slight gradient Sensitive tapping zone Underpass Section A-A A 51

T.N. T.N.

Natural ground Natural ground

Schéma : solution retenue. Rivière de la Gresse

Diagram: chosen solution River Gresse

P.S. Passage agricole Merlon Faible pente Zone sensible / Captages P.I. Coupe A-A A 51 Casiers hydrauliques T.N. P.L. A51

Overpass Agricultural route Earth mound barrier Slight gradient Sensitive tapping zone Underpass Section A-A A 51 Hydraulic strips Natural ground Adapted longitudinal section of A51

Merlon Pente douce

Earth mound barrier Gentle gradient

T.N.

Natural ground


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E – Preparation of work E.1 – Design and analysis of variants E.1.1 – General stipulations and stipulations in regulations Article 50 of the Procurement Contract Code allows bidders to submit tenders with variants at the same time as the basic solution, unless there is an express indication to the contrary in the public invitation to tender and in the rules for tendering. The rules for tendering should indicate the general limits for the variant solutions. In their assessment of tenders, the authorities awarding the contract (PA) are obliged to examine responses to the basic solution before the variant responses. They must then examine the basic offer of the best candidates with the most interesting variant solutions in order to determine the most advantageous economic bid in accordance only with the criteria set in the rules for tendering (article 53-V of the Procurement Contract Code).

E.1.2 - Application to earthwork sites Approved principles: Any ”variant” leading to modification of the project’s geometry (the land requirement or the red line) is excluded on the grounds of the unchangeable points constituted by the heights of structures, restorations of roadways or hydraulic structures built. Proposals in relation to materials, products or specific methods of execution to provide the basic solution for the contract are to be examined within the context of preparations and acceptance of the Quality Assurance Plan (PAQ), and are therefore not considered as variants. We may thus set out a priori (as a non-exhaustive list) several earthworks variant families, as follows: • variants for stipulations concerning sewerage or drainage; • variants for consolidation of structure parts; • variants for materials to build the embankments/fills; • variants for road support platforms (upper parts of earthworks and/or capping layer); • variants for timelines for structure (economic timeline, partial timeline / optimization of equipment fleet). As a general rule, sewerage, drainage, and the choice of solutions for consolidation and reinforcement (compressible soils, stiffening of slopes, etc.) are the result of studies at project level by the construction manager designer which have led to designs of structures and are not usually open to variants, particularly when a procedure in advance has established State commitments (the Water Act in relation to sewerage or drainage). However, if this variant option is authorized, the DCE should be accompanied by studies in sufficient detail to ensure the feasibility of variant studies and set out the following in the rules for tendering: • that the studies for design and execution of the variant, and any subsequent modifications, are the responsibilities of the contractor, and that the corresponding price covers all the normal tasks of a construction manager in terms of design; • that the variant must not affect the rest of the design of the structure; • that the variant must not involve any prolongation of the overall timelines for the operation; • that if the variant proposed does not meet the above criteria, it will be removed from the bid; • that if, during the period of preparation and during site work, the performances set out in the variant solution are not confirmed, the contractor must suggest technical readjustments to its solution with no modification of the initial cost of the variant. A return to the basic solution is not authorized with respect to the initial call for tenders. With respect to the materials used to build the embankments/fills, in general a distinction is made between the following two cases: • Is the earth moving balanced (study carried out when the DCE is drawn up)? No variant (details of earth moving will be specified and validated in the Quality Assurance Plan PAQ); • Does the DCE envisage filler materials for embankments/fills? Contractors’ proposals are judged in terms of their conformity with the rules of the GTR Technical Guide to Embankments & Fills rules and their adaptation Collection « Les outils” – Sétra

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to design of the structure (gradients of slopes, rigidity of the upper parts of earthworks, permeability, etc.). These proposals do not therefore constitute variants. Special cases are possible, however. By way of example, the case of an embankment in a area liable to flooding - the DCE envisages construction of the lower section of the embankment with non-water sensitive materials as part of the basic solution. Variants in terms of the nature of materials may thus be authorized (for example, soils treated with a view to preventing capillary rise or wake wave erosion of taluses).

E.1.3 – Plausible variants Variants authorized and often justified thus relate to the design of the platforms. They may be classified as three main types: • type 1 variants leading to construction of the same platform. Here there are no consequences in terms of the road structure; • type 2 variants leading to construction of a class (i) upper platform. Here there are consequences in terms of the sizing of the road structure. This type of variant is generally permitted only if it involves a single earthworks-road contract, or a contract with an earthworks section and a roads section; • type 3 variants introducing the consideration of mechanical performances of the capping layer and sizing of the platform/road unit using a structure calculations model; In parallel fashion to these variants, a variant may be superimposed on the means of execution: higher-performance spreading and grading methods, allowing the contractor to meet the requirements of more stringent leveling tolerances than those specified in the basic solution or identical PF, reduction of the road structure (in the case of earthworks-road contracts).

Type 1 variants Their characteristics are generally as follows: • either improvement of the subformation by treatment or substitution and lesser thickness in the capping layer; • or a variant in relation to the nature of the untreated material specified in the basic solution for the capping layer (a proposal to use industrial by-products, for instance); • or a variant with treated soil to replace the untreated material specified in the basic solution for the capping layer; • or a variant in relation to the mechanical performances and thickness of the treated soil specified in the basic solution.

Type 2 variants These variants may related to the thickness and/or the nature of the untreated material specified for the capping layer, as per the upgrading rules in the GTR Technical Guide to Embankments & Fills [10]. In most cases, this involves using the possibilities available in the Guide to Treatment of Soils (GTS) [13] for the sizing of treated capping layers: • change in the method of treatment; • change of binder; • change of proportioning; • change of mechanical class; • change in thickness.

Type 3 variants These variants will be acceptable only in the case of very large sites (such as motorways), where extremely stringent quality assurance stipulation are implemented, and where correction of the road structure may be envisaged if it proves impossible to obtain the mechanical performances in the capping layer, for sizing of the structure.

E.1.4 – Technical analysis of the variants When the rules for tendering authorize the variants, the project owner is compelled to include the conditions Collection « Les outils” – Sétra

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which must be met by the variant solutions. To this end, the person writing up the rules for tendering (RC) may use the indications in the Guide to Treatment of Soils (GTS) in the case of treated capping layers, or use this for inspiration in the case of variants involving untreated materials. The writing criteria are in accordance with: • contract context types (see items furnished in the GTS Guide to Treatment of Soils pages 147 and 148 [13] in the CCTG General Technical Specifications’ section 2 [49] and in the guide to drafting the Particular Technical Specifications (CCTP) for earthworks [19]; • specifications to be included in the CCTP and requests to be made for response in the quality assurance plan’s organizational chart (SOPAQ) for judgment of the variants (see GTS Guide to Treatment of Soils, article C3 1.4 pages 153 - 155) [13].


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E.2 – Legal, technical and economic risks in relation to earthworks E.2.1 – Risk assessment Risk is normally the unknown factor present within a project designed and carried through to the rules of construction. With respect to earthworks, as in other areas, risk may be legal, technical, economic or even political.

E.2.2 - Legal risks in relation to earthworks During the study/design stage, the consequences of risk are not necessarily immediate. However, legal disputes may often arise subsequently during the actual works phase or after commissioning if, during this study/design phase, procedures have not been implemented, measurements have not been taken, or reports have not been drawn up. Risk concerns mainly the following:

Borrowings and deposits of materials A lack of knowledge of the administrative procedures in force, both in terms of the Mining Code [51] and impact studies, may lead to a situation in which the builder does not have the required materials or deposit sites readily available. To prevent this type of risk, there must be commented distribution of the procedures in force. With regard to this, the matter of the legal status of surplus materials, particularly in terms of their utilization in other operations, must be clarified at interministerial level. There are, in fact, restrictive interpretations of texts by the DRIRE currently emerging in relation to surplus materials. Are these natural deposits, items in storage or depots? The law governing waste, however, considers that all surplus materials not reused on the site land requirement constitute waste, and must be managed as such. The planner must therefore concern himself at the earliest possible stage with balance in terms of earth movement in all cases as of the preliminary design [APS]. He will set out needs in terms of borrow materials and deposit sites. This matter is to be discussed in the impact study in the public interest inquiry report (the decree of 25 February 1993 and the circular of 27 September 1993 from the Ministry of the Environment state that borrowings and deposits must be treated as indirect effects of the project). In the case of smaller projects, borrow and deposit locations may be located as of the acknowledgement of public interest (DUP), in view of their considerable incidence on the cost of earthworks, and also on the nuisances caused to local residents by heavy goods vehicles.

Blasting earthworks During blasting operations there is a risk of damage to the surrounding built structures, and this generally creates legal cases between the contractor and local residents. The incidence of these situations may entail a site shutdown, with all its financial and technical consequences. To prevent this contingency, it is advisable to first identify sensitive areas and then seek to use the services of companies with wide experience in rock earthworks. In terms of quality procedures, it is also advisable to request specific qualifications for this type of service. In any case, an inventory report for the inside and outside of buildings before and after blasting operations is essential.

Checks on piezometric levels Here a distinction may be made between the risk of recession in springs and wells and the consequences of lowering the water table on the natural and agricultural environment and availability of drinking water supply. In order to avoid any risk of legal cases relating to recession in water supplies for human, agricultural or industrial use, at the very least a hydrogeologist must draw up joint reports prior to operations on water levels (establishment of the environmental guide to be supplied, etc.). Collection « Les outils” – Sétra

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For measurement of water level variations in proximity to the site and also at a distance of 70 or even 100 meters, and the incidence of the various phases of work on the surroundings, it is advisable to implement piezometers on a line perpendicular to the project. Restoration of usage will often involve direct financing of damages by the project owner through an agreement with private individuals, if they have not been taken into account in work relating to a land reallocation, for example.

Falling sections Neglect of or failure to take sufficient consideration of this risk has technical and financial consequences in particular. In the case of a poorly designed project, however, an accident may entail penal consequences for the project owner and the construction manager, or possibly the engineering firm in charge of design and / or the contractor.

E.2.3 – Technical risks in relation to earthworks Risk is most often of a technical nature in relation to earthworks. It often concerns the following non-exhaustive list:

Quality of geotechnical studies Technical risk in terms of earthworks mainly stems from a lack of knowledge of the geotechnical and hydrogeological contexts. The importance of geological and geotechnical investigation can never be overestimated. This must be adapted to the development of studies in connection with basic design, the size of the project and the geological and topographical complexity of the site (see the LCPC document Commande et contrôle des reconnaissances géotechniques de tracés (Command and control for geotechnical investigation of alignments) Ref. 59023101). The project owner is responsible for carrying out all studies in the proper fashion (it should be borne in mind that the overall costs of studies for an operation are between 2% and 9% of the operation, in accordance with the size of the operation and the type of services provided as in-house works or subcontracts). There should never be deadlock for reasons relating to finance or timelines. The first error is neglecting preliminary studies (preliminary studies [EP] and overview / background summaries [APS]). Over the last 25 years, the considerable importance given to environmental constraints, and more specifically the constraints of the natural surroundings, have meant that designers tend to attach less importance to geotechnical constraints proper, which are rarely the main factor in terms of choice of variants, and they concern themselves with these constraints only at an advanced stage of the project. This means that technical anomalies which could serve to alert designers to carry out in-depth studies in good time on such singular matters are not identified at a sufficiently early stage. Similarly, it is advisable to attempt to gather together investigation data for the entire project. If topography renders land inaccessible, this could in fact signal that the land is unstable. With no exceptions, inaccessibility of land in terms of either topography or refusals by land owners cannot lead to deadlock on a certain area of the project.

Falling sections From the technical point of view, a distinction is made between the risks of falling sections from slopes outside the land requirements and falls from slopes which form part of the project. In rocky areas, this must be a concern from the outset of studies. Beyond repercussions in relation to the choice of alignment, the incidence of this risk may lead to a choice of building retaining walls rather than earthworks slopes, building stone traps on the edges of the construction, and/or consideration of building protective structures on slopes.

Limited or insufficient material resources In addition to the legal risk mentioned above, failure to appreciate earthworks balance generally leads to underestimation of this item. Collection « Les outils” – Sétra

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There are many causes. If systematic use of programs to calculate earthworks volumes and digital models has made calculation of geometric volumes easier and reliable, it may frequently be observed that no account is taken of all items which may affect the conditions for reutilization of soils (bulking, for instance).

Areas of low bearing capacity and compressible areas In due consideration of the fact that these areas could call the project into question or create considerable technical constraints, it is advisable for work to be carried out with a geologist to identify such areas as soon as possible visually in preliminary studies, proceeding with technical identification during the overview / background summary [APS], and subsequently during the actual project phase. Building an embankment too rapidly on soil which is compressible and/or has a low bearing capacity can entail general instability in the bearing soil and the main body of the embankment. Beyond the safety problems engendered by collapse of bearing soil and an embankment, stabilization work, treatment of the area and rehabilitation of structures will require substantial additional costs and prolongations of timelines. In the specific case of embankments/fills on compressible soils, in addition to stability problems, there are two other basic problems to be addressed: the deformations caused, in particular, by settlement of the bearing soil under the embankment (settlements in the short and long term, with creep to be considered in future years, and over many years in fact), and the strains caused on surrounding structures (either already built or to be built at some future stage). For the construction of embankments/fills on compressible soils, the consequences on the handling of the project relate to four main points, as follows: • problems in connection with the feasibility of the structure: an embankment built on compressible soils could entail specific construction stipulations such as the use of vertical drains, construction of bench terraces, construction in stages, implementation of temporary overloads, etc. • phasing of particular tasks, especially in terms of building structures and their foundations in particular; • operating constraints, especially permissible settlement in the long term at platform level; • time: whether in terms of studies, actual work or consolidation of soils and monitoring of this, time will be much more important than in the construction of a ”classic” embankment. In cut areas, soils with a low bearing capacity must be purged or treated with hydraulic binders, and must not constitute a water trap.

Unstable slopes It is advisable that the preliminary studies identify areas with a risk of unstable slopes (consultation of the PPR plan for prevention of foreseeable natural risks should not be neglected). A simple analysis of geological and geomorphological charts and a compulsory visit to the site in order to examine its topography, position of trees, bushes, fence posts, etc. will reveal areas which are unstable or could become unstable. In geotechnical studies during the phase of the overview / background summary [APS] and the actual project phase, the geologist will draw up an evaluation report of uncertainties within the study. When stability studies specify the construction stipulations to be enacted, deadlock must never be reached in relation to such stipulations on the pretext that the slope is stable during the construction work phase.

Underground cavities Natural or man-made underground cavities may affect the structures (collapse, subsidence, etc.). It is therefore extremely important that areas which may contain these cavities be identified as early as possible in the preliminary studies. The initial procedure will be a visit to the site, a local inquiry and collation of information from specialists such as BRGM, DRIRE, CETE, DDE, and the Préfecture's civil protection service. In order to adapt treatment of the cavity, the costs of which are sometimes considerable, the uncertainties should be characterized (type of cavity, size, diameter, depth, density, quality of the vault, etc.).

E.2.4 – Economic risks in relation to earthworks Beyond the economic effects of legal, technical and meteorological risks, insufficiencies, inaccuracies and Collection « Les outils” – Sétra

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inconsistencies in connection with the various sections of a work contract are often the cause of litigation and shifts in costs. The following are the main points to be observed: • words in written texts which have no meaning. For example: - deep water - moderate settlement - protection against runoff water - construction constraint as the result of … - imperfection - the contractor will deem it necessary to … • text that imposes unrealistic obligations on the construction manager; • make progress subject to decisions by the construction manager (risk of site shutdown, selection of the real stoppage points); • stipulations in the CCTP Particular Technical Specifications not included in the prices specification; • prices including services which cannot be provided; • inconsistencies between the provisions in the CCTP Particular Technical Specifications and the schedules of prices; • incomplete work and / or insufficient means with respect to the technical aspects or the quality required; • an absence of precision as to the deposit locations or transportation distances for deposits; • unit prices whose definition is too wide or difficult to estimate; Example of sensitive prices; ”whatever the material” ”whatever the volume concerned” • prices including risk on levels of performance or output; • complex prices which are charged at a flat rate or an inclusive fixed sum; • quantities siphoned between several prices.


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E.3 – Phases prior to construction E.3.1 – Concerning the Tender Documents [DCE] during the period of preparation Warning Production of a full DCE and an excellent period of preparation are essential for a successful site. The first quality procedure consists of an excellent earthworks study by the construction manager on the basis of serious geotechnical studies, and a sound choice of the start date for earthworks operations. In relation to geotechnics, the DCE must contain the following, for instance: • a longitudinal section of cuts / embankments/fills with cubes for each cut and embankment; • a geotechnical profile with separation of materials and classification in accordance with the GTR Technical Guide to Embankments & Fills [10]; • a full geotechnical report, the bore file, and photos of samples; • seismic-refraction study for rocky soils; • all studies for embankments/fills > 10 meters on compressible soils, treatment studies and studies on stability of slopes; • the earth movement project. Constraints on choice must not be only in relation to budget; even if too often they govern the awarding of contracts or are dictated by functional or political obligations, they must also take account of the following: • periods favoring rational execution of work (climatic conditions, traffic constraints, etc.); • the load plan for all companies which affects prices; • a sufficient period of preparation for the contractor. For project management, this preparatory phase (DCE + period of preparation) prior to the start of major earthworks must include the following:

The pegging plan for the operation • The construction manager implements the axis, setting out planimetry and altimetry at each stake along the axis. The land requirement boundaries must also be made available to the contractor subsequently (planimetry only); • A joint report on pegging will be drawn up during preparatory work by the construction manager and the contractor after the latter has checked the pegging quality. Initial inventory • an inventory report for the land requirements, including the area containing the site facility (available parcels, unavailable parcels, parcels with crops); • if there is no approved route specified in the contract, a detailed inventory of routes which could be used by the contractor will be drawn up by the construction manager. The inventory report may be attached with the DCE if the routes constitute a major constraint in terms of transportation. Following acceptance by the project owner of this inventory and the conditions for rehabilitation of borrowed routes, the inventory report will be submitted to the contractor during the preparatory period. Following examination of the report, the contractor accepts the construction manager’s inventory, and the conditions of the project owner for the road, in due observance of article 34 of the General Administrative Specifications [CCAG] for works. If the contractor contests the inventory report, a rectifying report will be drawn up jointly by all parties and, following agreement by all parties, a route or routes will be approved by the construction manager. Displacements of networks • examination of maintenance of communication and water flows. A visit will be made to the site to set out the provisional stipulations which must entered in the DCE; • displacements of networks: on completion of the project report, the construction manager makes a list of networks with the concessionary companies, and, together with the concessionary companies, defines the displacements which will be respectively the responsibilities of the concessionary company and of the construction manager in accordance with jurisprudence in force, i.e.: • if the network to be displaced is located on private property, it will always be to the responsibility of the party requesting; Collection « Les outils” – Sétra

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• however, if the network is located on public property and road works are carried out in the public interest and constitute a development operation in accordance with the usage of this area, displacements are the responsibility of the concessionary companies (example: rectification of bends, roundabouts, etc.). For the concessionary companies, the criterion of the new structure, the objective of which was to systematically place the cost of displacements on the account of the project owner, no longer exists. Thus, between the Project phase and preparation of the tender documents [DCE] for Earthworks, the project owner must finance and arrange displacements of networks located within the land requirement or give the concessionary company notice to displace his networks. A summary of displaced or undisplaced networks must be drawn up and attached with the DCE or submitted to the contractor during the preparatory phase of work at the latest. For reasons relating to urgency or work order, temporary displacements, often by air, may be carried out.

Administrative authorizations for occupation of land • a copy of the temporary occupation agreements and, if any, road-using permits setting out the conditions for utilization of land and the nature of rehabilitation; • in terms of real estate, in accordance with the DUP acknowledgement of public interest, the project owner must undertake to always specify early possession of land in offers to sell. Likewise, when the land reallocation procedure is engaged and classification of land has been completed, he must request the Prefectoral order for early possession of land. Archaeological excavations • section 1 of the law of 27 September 1941 and the decree of 27 May 1994 stipulate that “no person may carry out, on land belonging to them or to others, excavations or bores for the purpose of investigation of monuments or object which may be of prehistorical, historical, artistic or archaeological interest without obtaining prior authorization”; • therefore any excavations for investigation, reconnaissance or rescue of any archaeological remains, where necessary, must be undertaken by bodies approved by the DRAC in order to conserve archaeological heritage; • any fortuitous archaeological discoveries must therefore be made known to the mayor of the municipality who must notify the Préfet without delay – in general, excavations will have been carried out by the project owner following approval of the project report and prior to production of the first DCE for works; • a check must therefore be run to ensure that all facilities, including the location of the main site, or earthworks, will be in areas that are cleared by archaeological agencies or departments; • the financing agreement for archaeological excavations must envisage filling of excavations and restoration of topsoil to prevent the trapping of water in holes. This practice will maintain a satisfactory moisture condition in the soils, and will also prevent excess loss of reusable materials, particularly when work is due to start 1 or even 2 years afterwards. This practice has the advantages of preserving the landscape and of saving costs for the entire operation. The costs of archaeological excavations may be extremely high, particularly when the site has a rich content of archaeological items, but also in the case of compressible soils. Estimates should be requested as soon as possible from the DRAC.

Conservation of the environment Noise • noise in connection to site activity creates sporadic nuisances for residents, disturbances in connection with fauna, and has harmful effects on the health of employees when they do not have protection equipment; • the construction plant and equipment used must, first and foremost, comply with the regulations in force concerning limitation of noise; • in accordance with article 12 of the law on noise, the project owner is bound to notify the Préfet and mayors concerned of the noise levels which will be created by the construction work, and the measures taken to reduce the expected nuisances; • the Particular Administrative Specifications [CCAP] should therefore state that the contractor must provide the construction manager with all the required items for this declaration as of notification of the site preparation period; • concerning noise in relation to rock excavation blasting operations, see chapter B10 of this guide. Flow of natural water • in the absence of specific stipulations in the DCE, modification of surface or subsurface flows during earthworks often entails pollution which can migrate outside the site; Collection « Les outils” – Sétra

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• it should therefore be borne in mind that flows of natural water are governed by the constraints in articles 640 and 645 of the Civil Code, namely: • lower courses are subjugated to those on a higher level to take in water flowing from them naturally without any human contribution; • the owner of the area above can do nothing to aggravate the constraint of lower courses; • if usage of this water or the direction given to the water aggravates the natural constraint of flow, an indemnity is owed to the owner of the lower course; • in order to reduce or eliminate any risk of pollution of natural and aquatic media, temporary sewerage systems on site must be specified in the DCE and renotified to the contractor during the preparatory period; • these measures for collection, storage, treatment and disposal in a natural outlet may be accompanied, where necessary, by suitable additional treatment: if the discharged rate of material in suspension is ≥ 150 g/l, approved flocculation agents must be used which are compatible with aquatic fauna; • particular attention must likewise be paid to large flows which could lead to a substantial increase in the flows of neighboring water courses which are incompatible with the equilibrium of aquatic ecosystems, particularly during spawning periods; • earthworks (cuts, embankments and fills) may modify the natural course of subsurface water and its flow. For this reason, an inventory and a list of the wells located within the immediate surroundings of the project (100 m on either side) will be drawn up before any work commences. Piezometers perpendicular to the project may be used to confirm or annul changes in the water table that supplies the wells (lowering of the water table, dewatering, etc.). Considerable modifications may lead the project owner to finance a new well. • during a prolonged period of drought, the Préfet occasionally issues a decree forbidding certain uses of water.

Atmospheric pollution • there are many nuisances created by dust, and over and beyond the safety and health of employees these also affect residents living in proximity to the site, although, due to the strength of the wind, also those who live at some distance from the site; • the chapter relating to atmospheric pollution caused by dust from limestone and cement is properly set out in the technical guide to treatment of soils (chapter 5.3 page 51). This document should be noted in the CCAP Particular Administrative Specifications, and particularly the paragraph concerned, or to take up the prescriptions in the Particular Technical Specifications [CCTP]; • in order to prevent flying dust, particularly during dry periods, the site, with particular emphasis on tracks used by machinery, must be sprinkled on a permanent basis; • when a drought decree is issued by the Préfet, earthworks sites are often obliged to shut down. The principles set out in the decree of 8 January 1965 (modified by the decree of 6 May 1995) authorize the head of the contractor’s company to take the initiative of sprinkling the site tracks for employee safety and thus to continue work (a decree overrules an official order). The use of water, however, to moisten soil whose water content is too low to make it reusable on part of the structure would not be possible in the event of a drought decree, and in this case the decree may not be evoked; • on another point, dust falling into water courses or areas of moisture will have an impact on the aquatic environment or will clog up areas of moisture. The presence of these environments in the immediate surroundings of the site must be set out in the DCE and renotified to the contractor during the preparatory period on site; • the use of industrial by-products or waste such as incinerator ash, for example, may create olfactory pollution in sensitive environments (habitats). Fauna and flora • in relation to fauna and flora, ecosystems and biotopes to be conserved which are located near the site and which have been fully identified in the preliminary phases of road studies (overview / background summary [APS], impact study, Water Acts, working design, etc.) may be listed in the Particular Administrative Specifications [CCAP] and made known to the contractor from the outset of the preparatory phase, to allow the contractor to avoid causing any deterioration due to dust, noise, leaching caused by non-natural surface flows, petroleum products, detergents, etc., in these sensitive, often listed environments, where the long-term quality of ecosystems and biotopes must be guaranteed.


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Safety on earthworks sites In addition to the requirements of legislation and regulations, safety must be present at all times from production of the DCE, during the preparatory phase, and on a permanent basis during the construction works phase. Safety is clearly of interest to work stations, but also in relation to the conditions of access to the site (geometric and structural characteristics of roadways, pollution on roads), on-site traffic (speed, dust, crossing of trafficked roads), storage and use of hazardous products (quicklime in all cases and especially in proximity to built-up areas or trafficked roads, explosives, etc.). In relation to work stations, the decree of 8 January 1965 modified on 6 May 1995 and applicable texts stipulate the minimum prescriptions applicable to building sites or public works. In relation to earthworks, the most important points concern the stability of earthworks slopes or walls for trenches, work by machinery on the edges of old or recent slopes or slopes with excessive gradients, the reversing warning signal on machinery, and light vehicle traffic.

E.3.2 – Inventory of the tools required for proper site construction The procedures listed below are the responsibility of the project owner and the construction manager. They must be implemented at the earliest possible stage so that they do not constitute either non-quality in production of the DCE and during site work, or a hindrance to sound site progress. 1) Master plan quality sketch (ESDQ). 2) Displacement of networks in public and private areas. 3) Taking up advance possession through offers to sell or a Prefectoral order for the land reallocation procedure. 4) Temporary occupation agreements. 5) Opening of quarries on the responsibility of the project owner if the materials are provided by him. 6) Archaeological excavations for the purposes of reconnaissance, investigation and safekeeping. 7) Authorization by the mayors concerned for elevation of soil beyond land requirements. 8) Authorization or declaration in relation to the Water Act. 9) The general safety and health coordination plan. 10) Prior declaration to the Préfet in connection with safety and health. 11) The declaration to the Préfet and mayors concerned in connection with article 12 of the law on noise (law of 31/12/92 + decree of 9/01/95). 12) Site operation. When operations concern a number of contracts and agents, especially in urban areas, it is preferable for the construction manager to draw up the site operation report in association with the management and field unit services. 13) Waste management in accordance with the law of 13 July 1992 and the circular of 15 February 2000. 14) The quality master plan (SDQ) in association with the contractor during the period of preparation. The procedures listed below are the responsibility of the contractor or the agent of the group 1) Opening of quarries if the supply of materials is the responsibility of the contractor. 2) The declaration of intent to commence work (DICT). This must also be addressed to the mayors (decree of 14/10/91 + order of 16/11/94). 3) The quality assurance plan (PAQ). 4) The environmental assurance plan (PAE) for certain types of site. 5) The site facility (decree 6548 of 1965 + 95-608 of 6/05/95 and the law of 19/07/76 + decree of 21/09/77). 6) Classified facilities (even in the case of a mobile crusher) and availability of surfaces. 7) The Special Plan for Protection of Health and Safety (PPSPS). 8) Site operation for simple sites in open country. 9) Authorization by the mayors concerned by elevations of soil outside land requirements. 10) Clearing and deforestation (attention must be paid to ownership of forests – see the offer to sell or the sale document).


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11) Building demolition (law of 13/07/92 on waste) – Provision of the organizational chart for waste management (this will also include management of other site waste in accordance with the law). 12) Production of price breakdowns. 13) Subcontracting. The contract binding the subcontractor to the contractor must be submitted to the awarding authority if the authority so requires. The contractor must ensure that the project owner accepts the conditions of payment for the subcontractor by provision of a subcontracting document. 14) Requests for acceptance of materials and products. These must be drawn up during the preparatory phase in order to give the construction manager time for verification. 15) Work plan and monthly financial accounts schedule. To be provided during the preparatory phase for sound management of time lines and payment credits.

E.3.3 – Earth movement and choice of materials Project earth movement plans There are three objectives in connection with earth moving: • connection via transportation lines of the needs established for a given project design to cuts of sufficient geotechnical characteristics, without neglecting an attempt to retain the best materials for the most salient parts of the structure or layers; • optimization of transport distances, with minimum total transport moment, while fulfilling the geotechnical requirements of the embankments/fills; • integration of special constraints such as obstacles which cannot easily be negotiated (roads with heavy traffic, railway lines, etc.), compatibility with work phasing and coordination with other types of work. Establishment of earth movements commences with a geometric analysis of each cut (site cuts and any borrowings), of the various parts of the structure of the embankments/fills (base of the embankments/fills, ordinary embankments/fills, upper parts of earthworks, capping layer, height of the embankments/fills, etc.), and with geotechnical analysis to meet the most salient needs possible with the best possible quality materials available, possibly treated or produced (capping layer, drainage bases, technical embankments/fills, extra-large embankments/fills, roadways, etc.), and to produce ordinary embankments/fills and structures requiring materials with lower levels of performance. Prior to establishment of earth moving plans, a geotechnical study of the project must be forthcoming (a constituent part of the DCE) with the agreement of the contractor, during the period of site preparation, as additional geotechnical investigation. This will enhance information as to the nature of the materials and their moisture condition, and will help with appraisal of the levels of reutilization in relation to the nature of soils. In the first outline of earth movements, the choice of material is not included, except perhaps in favor of certain types of extraction machinery for geotechnical or geometric reasons in connection with cuts, and certain ranges of transportation distances for economic reasons or reasons relating to the characteristics of site roads; this does not change the total moment. This initial earth movement allows definition of the material means chosen in accordance with the criteria described in the section below: “choice of earthmoving material”. The work schedule is thus drawn up by integrating earth movement, the estimated output of approved material resources, foreseeable inclement weather conditions and the various site constraints (phasing, obstacles, timelines, etc.). To optimize site execution, it is advisable to refine earth movement, choice of materials and the work schedule by successive iterations.

Choice of earthmoving material Extraction machinery There are two large families of extraction machinery, as follows: Blade machinery

Bucket machinery

Bulldozers

Hydraulic shovels Loaders


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Scrapers

The first family (blade machinery) is suitable for layer extraction, for loose or rippable materials, with averageto-dry water content for scraping machinery. The second family is more suited to “frontal” operations and for loose or rocky soils. Certain special extraction machinery such as draglines or bucket wheels may be used in special cases.

Transportation vehicles The choice of transportation vehicles depends on • three main criteria: 1) the transportation distance between the place of extraction and the spreading location; 2) the nature and condition of the cut materials; 3) the configuration of the transportation track: slope, bearing capacity, rolling resistance, etc. • four large families of machinery: 1) Pushing by tractor/bulldozer. This is limited to a range of 0 – 100 meters; 2) Scrapers. These are currently used up to 1,500 meters (maximum 2,000 meters); 3) Single-piece or articulated dumpers. Depending on the configuration of the transportation track, they are used over distances of 0 – 3,500/5,000 meters, or more, if road vehicles cannot be used (semi-trailers); 4) Semi-trailers. If the materials are not excessively adherent, they are used over distances of more than 3,500/5,000 meters.

Leveling or spreading machinery: The spreading conditions in the GTR Technical Guide to Embankments & Fills [10] are applicable: • scrapers are best suited to spreading in thin layers; • in most situations, spreading is carried out using the blade of the tractor/bulldozer, or the tamper; • leveling is generally carried out using a grader (whether or not power-assisted).

Compacting machinery: See GTR92 as to the possibility or impossibility of using each type of compactor in accordance with the material to be used on embankments/fills. This document also lists the outputs.

Material and outputs In relation to the geometric and geotechnical characteristics of French sites and the problems encountered during transfer of machinery between sites, earthworks companies are restricted to utilization of the ordinary material described below. The output of the various levels of earthworks depends on many factors, particularly the following: • the geometric characteristics of the structure; • the nature and condition of the materials; • past and present meteorological conditions; • whether or not there is any interference with other levels or other tasks; • site staff and management staff.


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Material

Characteristics

Average output for certain typical levels

Scrapers

Load capacities 15 - 40 T.

(D10 pushdozer + 631 scrapers) 4,000 – 6,000 m3/d

Single-piece dumpers


Articulated dumpers


(50 T shovel + 35 T transport vehicle) 1,700 – 2,400 m3/d

Hydraulic shovels • Major earthworks machinery

Machinery weight 35 – 85 T

• Other earthworks

Machinery weight 15 – 35 T

(35 T shovel + 15 T transport vehicle) 600 – 1,200 m3/d

Loaders

Buckets 1 - 6 m3

(5 m3 loader + 35 T transport vehicle) 2,200 – 3,500 m3/d

Tractor/bulldozers

Power output generally 100 – 400 cv, and exceptionally 600 cv

Graders

Power output generally 100 – 250 cv, and exceptionally 300 cv


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(85 T shovel + 35 T transport vehicle) 2,500 – 4,000 m3/d

March 2007


Choice of machinery The table below shows the material recommended for use in accordance with geometric, geotechnical, hydraulic and topographical parameters: Parameters Families of machinery

Types of machinery

Transport machinery

Dragline

Yes

Yes

Yes

repetition generally required

Yes

Yes

Scraper

Yes

Yes

Scraper

Yes

Single-piece d

Yes

Articulated d

Yes


Yes

Yes

Yes

vibrator tires tamper

Yes

Yes

Loader

Road truck

Compaction machinery

Geotechnical parameters

Hydraulic parameters

Topographical parameters

1,500 – Over Under Outsid 300 – Rippa Water Steep 3,500 m/ 3,500/ Loose Rocky w. e w. Tracks Roads 1,500 m ble % - IP ramps 5,000 m 5,000 m table table Shovel

Loading machinery

Geometric parameters (average transportation distance)

repetiti

repetition

Yes

Yes

Yes

Yes

Yes

Yes

low

Yes

Yes

low

Yes

Yes

Yes

low

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

low

Yes

Yes

mining

Yes

Yes

Yes

Yes

Yes Yes

Yes

Yes Yes (good tracks)

Yes

See GTR

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E.4 – Work phase E.4.1 – Procedures to be observed during the work phase The procedures to be observed are specified in the CCAG General Administrative Specifications for Works, the CCTG General Technical Specifications, regulations and guides, and in the administrative sections of the works contract. The works management guide published by Sétra as reference A9922 sets out in detail with occasional reference to jurisprudence all procedures relating to specific site situations during the works phase, namely the following: •phase 0 choice, preparation of contract and notification .................................................. page 13 •phase 1 site preparation .................................... page 25 •phase 2 tasks for execution .............................. page 32 •phase 2A technical problems in relation to quality ....................................... page 54 •phase 2B finance problems ........................... page 69 •phase 2C timeline problems .......................... page 86 •phase 2D administrative problems .............. page 100 •phase 2E difficulties in relation to the environment ........................................ page 118 •phase 2F safety problems ............................ page 159 •phase 3 reception and guarantee of full completion ......................................... page 166 With respect to timelines, when the bidder is obliged to submit documents which require time, it must be verified that the timeline in the bid is compatible with the duration of the studies to be carried out. Likewise, if certain work requires a certain amount of time during the site preparation phase– for instance, drawing up a geotechnical study of a sector that is initially inaccessible (due to refusal by the owner), or a study of formulation of treatment – then the timeline for the period of site preparation must be adapted. The CCAG General Administrative Specifications for Works and the decree of 2002-232 set a certain number of timelines which are summarized in the tables below.


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E.4.1.1 – Contract management - CCAG General Administrative Specifications for Works as completed by the stipulations of decree 2002-232 - Overall period for payment Art. CCAG

Main construction contractor or agent

Art. CCAG

Choice of address

2.22

Notifies the ”awarding authority” (PA) and project management ≤15 days after notification of contract.

2.22

Acceptance of subcontractors

2.41

Purpose

Communication 2.49.2 subcontracting contract

Service orders replies

Construction Manager

Ditto project management.

Request for acceptance sent to PA.

2.42

Reply within 21 days following request – implicit rejection failing this.

15 days after PA request, default penalties after 1 month application art. 49.

2.49.2

No reply > 1 month, application of article 49, formal notice period ≥ 15 days.

2.51

Addressed to the contractor in 2 copies, 1 of which must be returned to project management after signature with date of receipt.

15 days after reception of service order, in the form of a note to project management (50.11). 50.12

49.1

In the event of a failure to observe the service orders, formal notice with execution time ≥ 15 days.

50.12

decision notified to the contractor within 2 months of receipt of note – rejection failing this.

4.12

Absence of constitution or increase creates obstacle to issue of order.

10.34

Absence creates obstacle to regulation.

50.12

Decision notified to the contractor within 2 months of reception by project management of reserves – rejection failing this.

Project management sends note to PA with its opinion.

Possible guarantee

4.11

20 days after notification of contract or additional clause.

Supply of price breakdown

10.34

Mini timeline of 20 days following service for production request.

10.34

Production requested by service order, and timeline set at ≥ 20 days.

Notification Reports

12.4 12.5

The contractor may ask project management to draw up a report.

12.4

Reserves on report

12.4

15 days following date of report to issue written remarks 50.12 to project management.

Project management sets the date of notification within a period of ≤ 8 days of the date of request. Joint report drawn up immediately by all parties concerned.


Project Owner PRM

2.22

2.52 50.11

Failing this, notifications to the Town Hall.

Art. CCAG

Transmission to awarding authority of the note with its opinion.

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Contract management – CCAG General Administrative Specifications for Works as completed by the stipulations of decree 2002-232 - Overall period for payment Purpose

Art. CCAG


Art. CCAG


Project Owner PRM

Monthly account project

13.11

Draws up the account project before the end of each month.

Accepts or rectifies the account project, 3.II of notifies the the contractor by service Decree order of the status of the account, and forwards to awarding authority within 15 days following reception.

96 of Has a total of 45 Procurement days for payment Contract Code from the date of dispatch of the account project to project management (*).

Suspension of period for issue of order

13.23

Suspension terminates when project management receives the letter (with recorded delivery) transmitting all parts.

13.23

96 of Awarding authority Procurement notifies the Contract Code contractor of its motivated decision for suspension. Awarding authority has at least 30 days to proceed with payment after the end of suspension (*).

Final account project General settlement Issue of balance

13.32

Establishes the final account project within 45 days following notification of the reception decision or 15 days if the execution period ≤ 3 months – penalties failing this (20.3).

13.22

Art. CCAG

2.I of the Decree

13.34 13.41 13.42

General settlement is contested 13.44 Claim note addressed to project management within the period of 30 days following the date of notification of general settlement if execution period ≤ 6 months changed to 45 days if > 6 months. Acceptance assumed failing this. Work not envisaged

14.4

Provisional prices


Observations submitted to project management within 1 month after reception of service order notifying prices accepted by default,

Project management requests suspension of the time period from the awarding authority.

Project management 96 of accepts or rectifies Procurement the final account Contract Code project and notifies the general settlement within: 45 days after date of submission of project; or 30 days after publication of review index; period of 45 days changed to 1 month if execution time ≤ 3 months. 50.12

50.12

Forwards the claim note to the awarding authority with its opinion.

14.1

Notifies the contractor by service note of work not envisaged. If not included in service order, provisional prices are

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14.5

Has an overall period of 45 days for payment of the balance from the date of acceptance of the general settlement (*).

Proposes settlement of litigation in the 2 months following submission of the note to project management – failure to reply means rejection.

Following agreement to curtail final prices. - Additional clause - Additional prices specification. - Additional list of March 2007


but not final


notified by additional service note within 15 days of the previous.

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overall prices

March 2007


Contract management – CCAG General Administrative Specifications for Works as completed by the stipulations of decree 2002-232 - Overall period for payment Art. CCAG


Art. CCAG


Increase in the work tasks due to a change of needs or conditions of use

15.1 15.2 15.22

Notifies his refusal to execute in writing to the awarding authority with copy to project management, within 15 days of receipt of the service order.

15.22

Notifies the order to execute the work by service order.

The sum of the contract is exceeded

15.4

Informs project management within 1 month after the sum of the contract has allegedly been exceeded.

15.4

Forwards to the awarding authority

If notification of commencement > 6 months after notification has a period of 15 days form the commencement service order to request termination in writing – failing this, the right to termination is lost.

19.11

Purpose

Commencement of work

46.6

General implementation plan

Programming of execution of Safety and Health Plan


The awarding authority takes or does not take the decision to continue.

49.1

If the contractor has not requested termination, formal notice by the awarding authority and possible application of 49.2.

Notifies the contractor of the decision of the awarding authority 10 days prior to the estimated date on which the sum of the contract was exceeded. Notifies the contractor of the foreseeable estimation of work tasks within 15 days of the previous service order. Notifies commencement of work by service note within 6 months of the date of notification of the contract.

Project Owner PRM

15.4

15.5

27.1

28.2 28.3

Art. CCAG

Notifies the contractor at the latest 8 days after notification of the contract or at the same time as the service order for commencement of work.

Submits for approval by project management < 10 days before the end – 172 –

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of preparatory period, failing this period < 1 month after the date of notification of the contract.


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Contract management – CCAG General Administrative Specifications for Works as completed by the stipulations of decree 2002-232 - Overall period for payment Purpose

Art. CCAG


Art. CCAG


Demolition of constructions

31.91

Request to project management 8 days before execution

31.91

No reply within 8 days – authorization assumed.

No usage for equipment and materials

37.2

Execution within the next 30 days following formal notice.

37.2

Draws up a service order requesting rehabilitation, with no action requested of awarding authority a formal notice.

Reception Prior operations

41.1

Informs project management and awarding authority in writing of the estimated date of termination.

41.1

Decision of reception

41.6

41.2 Remedy for imperfections within the period set by awarding authority in its decision, by default 3 months before expiry of the guarantee period.

Imperfections and defects

Notifies the contractor and proceeds with operations within 20 days of request or envisaged termination.

Art. CCAG

49.1 37.2

41.3

Advises the awarding authority as to the date. Draws up a report immediately. Informs the contractor of the proposal to awarding authority within 5 days.

41.6

Project Owner PRM

Formal notice issued with no result > 30 days permits automatic execution.

The decision of the awarding authority is notified within the 45 days following the date of the report on operations. If there is no decision within this period, project management proposals are assumed to have been accepted. If no execution within the period, may be executed at the expense and risk of the contractor.

Documents to be supplied after reception

40


At the time of the request: Notice of functioning and maintenance 2 months after reception: DOE Execution Conformity Documents.

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E.4.1.2 – Contract management – settlement for subcontractors The specific stipulations for subcontractors’ settlements (13.54 of CCAG General Administrative Specifications for Works), as completed by decree 2002-232 concerning the overall period for payment, are summarized below: Subcontractor

Forwards justificatory parts to the main construction contractor or agent.


Project Owner PRM

Accepts or refuses the justificatory parts within 15 days of their date of reception.

Accepted Forwards to the construction manager the account project accompanied by a certificate of acceptance, setting out the sum to be settled to the subcontractor (art 13.51).

If within 15 days of reception the contractor has not made known his opposition, the parts are considered as accepted. If the contractor has not refused or forwarded to the construction manager, the subcontractor forwards directly to the construction manager a copy of his account project accompanied by a copy of the recorded delivery of his dispatch to the contractor.


Refused And notifies the subcontractor of his motivated refusal

Directly advises the subcontractor of the date of reception of the account project and the certificate, and the sum due in his favor, and forwards the settlement statement to the awarding authority within 15 days of reception of the project. (3.II of decree 2002.232)

Has an overall payment period of 45 days from the date of submission of the account project to project management (art. 96 of the Procurement Contract Code). Sends notice of issue of the order to the contractor and the subcontractor.

Formally notifies the contractor by letter with recorded delivery to prove he has opposed a refusal within 15 days. Informs the subcontractor of the date of formal notice. Requests suspension of the period for issuing the order Notifies the contractor of his from the awarding authority. motivated decision for suspension. Has an overall payment period of 45 days as above. However, if the period remaining from the date of suspension is < 30 days, then this is changed to 30 days (arts. 2 and 4 of the decree).

The overall payment period includes: • • • •

intervention of project management (15 days maximum, art. 3. II of the decree), intervention of the awarding authority, processing by the public accountant (15 days maximum, art. 7 of the decree), processing by finance bodies.


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E.4.2 – Ordering of tasks Preamble An earthen structure, although occasionally complex (see preceding chapters, particularly the chapter on special structures), is generally one of the simplest structures to build. Thus its user quality depends, more so than in other areas, on precision of command, preparation, site organization and the techniques of the various agents involved. Again, more so than in other areas, quality control depends on the involvement of all concerned. The formalism of the procedure, described below – and which could perhaps be summarized as “write down what we intend to do, do what we wrote down, write down what we did, check that we did well what we wrote down, and keep what we wrote” – is absolutely necessary and must be strictly observed. Quality is a whole which is not just the production of documents (ESDQ, SOPAQ, PAQ, SDQ, etc.), but covers all the phases of studies for preparation of the project and execution of the works. A good geotechnical survey, good adaptation of execution times to the periods to be observed in relation to regulatory procedures (classified facilities, etc.), thorough study of the project file by the contractor, and thorough site preparation are all factors that will contribute to superior quality on the ground. Producing paper is not an end in itself, and is definitely no guarantee of quality. For example, a quality organization note, the main feature of the contractor’s Quality Assurance Plan, may often be set out on three or four typed sheets if they provide a good definition of site organization (organization chart, the role of each person and particularly subcontractors, the means used, frequency and nature of checks, sensitive points and stoppage points, management of anomalies, and the first procedures required to start work). However, this must be a living document which evolves along with the site to make organization of the site increasingly efficiency. Quality is above all a state of mind and it is everyone’s business, at all times. Without this continuous collective involvement of all those involved, the objective has little chance of being met.

1 2 3 4 5 6 7 8 9 10

Nom de la tâche PERIODE PREPARATOIRE Présentation du DCE et du dossier géotechnique par le MOE Reconnaissances complémentaires Projet de mouvement de terres Provenance de la chaux vive Etudes de traitement des sols pour PST et CF Provenance des matériaux pour PST et CF Itinéraire de transport et modalité d’accès au chantier Etat des lieux des itinéraires agrées Etablissement du programme d’exécution

Task name PREPARATION PERIOD Presentation of the DCE and the geotechnical file by PM Further investigations Earth movement project Source of quicklime Soil treatment studies for subformation and capping layer Source of materials for subformation and capping layer Transport route and site access method Condition of approved routes Creation of the execution program

Nov. Dec. Jan. Feb. Mar Apr May Jun Jul Aug


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Preamble

Operations to be carried out by the construction manager N°

Operations

Documents to be submitted and materialization

Production time

1

Plans for definition and longitudinal sections

Plans, longitudinal sections

On notification of the period of preparation

Listings of current section and restorations.


2

Data from computer calculations for definition of horizontal axes and longitudinal section Execution drawings (1)

List of cross sections and type cross sections


4

Plans of known networks

Plans

As above

5

Main precision traverse line

Situation plan Posts Traversing

1 month after notification of the period of preparation

3

6

Plan of land requirements Plans and listings of posts Demarcation General pegging

7

Period for a response by the contractor

Possible remarks before the end of the period of preparation


Plans, listings of singular 1 month after notification Investigation report at the points and pegging of the period of end of the period of preparation preparation

8

Plans of safety equipment Operating report and provisional signing (1)

9

Provision of terrain, provision of land requirements. Inventory drawn up jointly by all parties concerned.

1 month after notification of the period of preparation

Parcel plan, investigation 1 month after notification Drawing up the joint report on demarcation of the period of report by all parties with joint signature preparation concerned no later than at the end of the period of preparation

(1) Insofar as these execution documents, drawn up on the responsibility of the roads manager, are the responsibility of the construction manager


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Operations to be carried out by the construction contractor The period of preparation must be adapted in accordance with the size of the site and the specific studies to be carried out before any actual work begins. This period may commence: • on notification of the contract (this solution is not recommended); • with a specific service order (recommended solution, set out in the tables); • with a service order for commencement of work when it is included in the period for execution. The periods shown are for information purposes, and may be modulated in accordance with the size of the site and the nature and complexity of the work to be carried out. N°

Operations


Production time

Maximum period for a response by the contractor

Additional geotechnical investigation

Bores Report, plans, test results

1 month 1.5 months after notification of the period of preparation

7 days (opinion of external check)

Earth movement project and topsoil movement plans

Plans, longitudinal sections, graph tables

End of the period of preparation and at least 15 days before the commencement of earthworks

15 days (opinion of construction manager)

General work program

Explanatory note Schedule (1)

10 days before the end of the period of preparation

10 days

Site facilities project

Paper + Plans


7 days

Papers, documentation, samples, test results

5

Proposal for origin and nature of materials for embankment, upper parts of earthworks, capping layer (3)

1 month before the commencement of supplies for each of the parts of the structures concerned


Papers, formulation studies, test results

6

Studies of treatment of soils for embankments/fills, upper parts of earthworks, capping layer (3)

1 month before commencement of treatment for each of the parts of the structures concerned


Program for studies and submission of execution plans

Program

7

1 month after notification Opinion of construction of the period of manager preparation In 15 days

Establishment of framework for Quality Assurance Plans and the Environmental Assurance Plan (PAE) (stoppage point)

Note on general organization

1 month after notification 15 days of the period of (approval of construction preparation manager)

1

2

3 4

8

9

10

Quality Assurance Plan for 15 days before the date Studies of the meeting for commencement of studies Model of monitoring files, 15 days before the end of checking plans, list of the period of preparation stoppage points and critiques, procedures for execution, etc.

7 days (approval of construction manager) 15 days (approval of construction manager)

Safety and health protection

PPSPS Members of CISSCT representing the contractor

40 days after notification of the period of preparation

Acceptance by the coordinator

Financial program for work

Monthly foreseeable statement of expenses

1.5 months after notification of the period of preparation

Not applicable


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March 2007


Preamble Operations to be carried out during the work stage Documents to be submitted and materialization

Operations

Breakdown

11

Breakdown of unit prices (with the exception of those submitted in the bid) Declaration of intent to commence work (DICT)

Letters to services 15 days after notification concerned (EDF of the period of electricity supply agency, preparation PTT postal service, drinking water supply agency, etc.)

Not applicable

Operating reports for traffic work (2) (3)

Reports

2 months before commencement of work on the section considered

15 days (4) (acceptance by the construction manager following opinion by the roads manager)

Transport route

Plans Diagrams Notes, inventories drawn up jointly by all parties concerned


15 days (acceptance by the construction manager following opinion by the project owner of the routes used)

Provision of company laboratory

Certificate of calibration of equipment

1 month after notification 15 days (acceptance by of the period of the construction preparation manager)

12

Production time


N°

End of the period of preparation

13

14

15

Execution plans (2) 16

Not applicable, unless there is any inconsistency with the prices specification

1 month before execution Approval 15 days after of the part of the reception of the structure concerned documents

(1) The “railway” diagram seems to be the most suitable for major earthworks. (2) If left to the contractor (to be avoided in general). This document must be drawn up on the responsibility of the manager by the construction manager. (3) Services to begin during the period of preparation, in due consideration of the periods required for their execution, and to be continued after the service order to start work. (4) It should be noted that, for major routes, the CRIR requires a reply period of at least 6 weeks.


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Preamble Operations to be carried out during the work stage N°

Operations

1

Acceptance of subcontractors

2

Special subcontractor document


Production time


2.5 months before commencement of work by subcontractors

21 days (acceptance is issued by the project owner)

Special subcontractor document

2 months before commencement of work by subcontractors

2 months

Subcontractor Quality Assurance Plan

Report with special subcontractor document

In accordance with the work progress made, 30 days before their commencement

15 days for approval by the construction manager

4

Evolution of Quality Assurance Plan

New procedures, updating of procedures

In accordance with the work progress made, 30 days before execution


Updating of the program for execution

Schedule

5

Partial schedule every 15 7 days for approval by days and every month for the construction manager the general schedule

Specific detailed programs, partial programs, site report graph

Schedules, plans, notes on specific stipulations

In general, every 15 days

Updating of the financial program

Accounts schedule

Every 3 months

3

6

7


Validation tests (stoppage point) including: 8

- acceptance of site shops Material description files

15 days before commencement of each

- evaluation of the procedure for execution

The first day of execution 1 day to lift stoppage point


Results of checks and report

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3 days to lift stoppage point

March 2007


Preamble Operations to be carried out during the work stage N°

9

10

11

Operations


Production time


Check on work

Daily monitoring reports, Every day report on tests, checks and daily updating of quality file

Identification of materials for embankments/fills or deposit, and materials for upper parts of earthworks d i l

Results of tests and reports, adjustment of thicknesses of layers and (or) material

Q/S compaction

Tachometer disks - report Every day

Bearing capacities in the main body of b k /fill

Results of bearing capacity tests

See CCTP

Conformity of subformation (stoppage point)

Results of measurement of bearing capacity Results of geometry check (topographical di )

End of earthworks on 10 days to lift stoppage section for reception, and point at least 10 days before commencement of i l

Conformity of capping layer (stoppage point)

Ditto subformation

End of work on the section considered


Conformity of geometry of cuts (stoppage point)

Cross sections

10 days before implementation of capping layer


Updating of earth movement plans

Plans, longitudinal sections

At least every 2 months

Implementation of axes before conformity report on capping layer

Listing Pegging of axis

15 days before reception of capping layer


Every day

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March 2007


Preamble Operations to be carried out on completion of work N°

1

Operations


Production time


Quality Assurance Plan completed

All items making up the Quality Assurance Plan

2 months after report on pre-reception operations or after execution of structures

7 days for verification of the contents

Conformity of drawings with execution of the structure

All plans sent to the contractor by the construction manager in the contract file with updated site work, movement of earth carried out, and execution plans drawn up by the contractor Tracings, copies, digital supports, notes, reductions

2 months after report on pre-reception operations or after execution of structures

15 days for verification and any remarks

2


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March 2007


F - Pathologies F.1 – Pathology of earthworks structures F.1.1 - Preamble Here we exclude special earth structures such as walls in reinforced earth, treated capping layers, etc., which require special techniques and have their own methods of execution, and will focus exclusively on the pathology of ordinary cuts and embankments/fills.

F.1.2 – Pathology of cuts The equilibrium of a cut slope relates to its geometry (height, slope), the characteristics of the soils and rocks, and the hydrogeological context. Weather conditions can also create structural damage, especially when weather conditions are exceptional. Instabilities in cut slopes most often appear between a few months and several years after work has been completed. Slides are often related to the following: • inappropriate slopes, often too steep for the soils; • water in a geological formation uncovered by the cut can lead to extremely unfavorable conditions for earthworks slope stability. This problem is often revealed on site work, particularly if the site has a wintertime. Superimposed permeability-heterogenic formations on a slope most often introduce water into slopes and frequently cause structural damage; • abrupt relief, as in a mountainous area, where earthworks slopes cannot be sufficiently inclined among some very steep natural slopes, and where unstable cliffs or slopes are occasionally carved out; • erosion of sandy or silty soils with no protection against gullying. Prevention of this kind of structural damage is the result of appropriate design. There must be knowledge of the soils and rocks to be used in earthworks for appropriate sizing of the slope and possible protection of the slopes on the cut and the land requirement to be reserved. Extra-high slopes merit particular attention, and usually a specific soil mechanics study. Geotechnical studies must prevent the discovery of these difficulties during site work since they often produce substantial extra costs, which will be claimed by the contractor experiencing difficulties in the orders for work to be carried out, and the site or user safety may also be compromised. As a general rule • it is usually preferable to opt for a light embankment rather than a light cut; • beyond essential research to integrate the project into the landscape, it is advisable to make the gradients of earthworks slopes more gentle, with or without support at the bottom; • the most common slopes used on cuts are two high-three at base for relatively stable soils, and one high-two at base for shaley and plastic materials. These slopes, however, can be subvertical in healthy rock with no cracks (or with cracks which have favorable orientation), and can be one high-three at base in the case of sensitive clays found in certain regions. The sizing of these slopes must take into consideration the hydrogeological context, and may occasionally require drainage measures such as shields or trenches; • it is advisable to quickly implement surface protection (topsoil and grass, and occasionally heavier or more sophisticated items) on the recently graded slope when the soils of which it consists are erodable, in order to prevent gullying related to rain or frost. Special systems and devices may be used and designed during site work to deal with structural damage, in order to: • drain off water that makes the earthworks slope unstable (shields, drainage systems and subhorizontal drains are the most frequently used); • provide a base abutment where we observe the beginning or the possibility of a slide (support, gabions, shield, bolts, etc.); • reinforcement of a rocky slope to prevent falling rocks (nets, anchorage, various structures, etc.); Collection « Les outils” – Sétra

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March 2007


• improve the surface stability of soils against the risk of erosion (a number of claddings for the slope, grass sowing, etc.). The pathology of cuts is most often due to unstable earthworks slopes. There are, however, other causes of structural damage, including the following: • interception of a water table by the cut. This should be detected by the geotechnical study, which then suggests a drainage device for proper site construction and to ensure the roadway will last; • insufficient surface drainage. Systematic questions should be asked on the routes available to water which has infiltrated the structure (bituminous concrete, even when properly constructed, can improve the runoff coefficient, but it is not impermeable, and infiltrating water cannot evaporate). Likewise, side ditches must be deep enough and maintained so that water ingresses do not moisten capping layers and bearing soil by infiltration into the main body of road; • incorrect transition between cut and embankment.

F.1.3 – Pathology of embankments and fills This subject was studied in France in a survey initiated by the Regional Public Works Research Laboratories in 1992 and completed in 1998 with an examination of 54 cases. A study was performed on the same subject by the PIARC World Road Association in 1997-1998, which studied 20 cases in 8 different countries and published the findings in its magazine Routes/Roads N° 306 in April 2000: “results of surveys on the pathology of operating embankments and fills” by J.C. Auriol, H. Havard, C. Mieussens and D. Queyroi. It was found that this type of survey was extremely difficult, and this explains the rather restricted number of cases studied. There are two main types of structural damage in relation to embankments and fills: 1) the “creeping” pathology of structures with slight deformations over several years before reaching an actual service level. A diagnosis is often only requested from a road-building expert 5 – 7 years after work has been carried out, since the pathology mainly consists of cracking in roads. In these conditions, it is generally concluded, erroneously, that the problem is due to insufficiency in the main body of the road, which is reinforced and will have to undergo maintenance work again 3 - 4 years later (or less), and so on, over a period of at least twenty years. Correlatively, this type of pathology, which is extremely characteristic of a faulty embankment, is only rarely attributed to faulty construction of the embankment, and will not emerge in an inquiry into embankment pathology even though it may be substantial. 2) a more obvious and immediate pathology (but also much rarer) involving break-ups and settlement which are sufficiently serious to require repair work, usually with interruptions in the flow of traffic. This type of structural damage often emerges not long after work has been completed, and is identified and reported as embankment pathology. These observations put into perspective the scope of the inquiries conducted and their representativeness in terms of statistics. We can, however, state the following on the basis of information collated by the inquiries: • 90% of structural damage reported in France stems from design flaws (poorly sized drainage facilities, unsuitably inclined slope) or flaws in execution (lack of compaction, deficient drainage, implementation in inappropriate meteorological conditions) which could have been avoided by improvements in competence and stringency of practices. Flaws in relation to surface sewerage and drainage of the land requirement constitute the main cause of the pathologies encountered in the above-mentioned inquiries. In the French inquiry, 33 of the 54 embankments and fills studied (or 2/3 of the pathology cases) manifested flaws in surface sewerage or drainage as the diagnosed causes of structural damage: • 75% of embankments and fills with structural damage were built with shaley material; • the steeper the slope of the embankment, the greater the risk of structural damage. We may point to the low vulnerability of embankment slopes built to the criterion of one high-two at base; • in approximately 85% of cases, structural damage was manifested by surface cracking. It is important to observe that structural damage observed on embankments and fills is most often due to several non-independent causes.


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March 2007


Thus, soil which can evolve mechanically after implementation and which has been used on embankments and fills with no obvious rigor can cause structural damage in relation to which it can be difficult to identify the main cause (is this the changeable nature of the material or defective quality of implementation?). In other words, a single flaw may sometimes have no consequences, but more often it combines with other weaknesses or flaws to produce structural damage, and there is often no point in searching for the main cause, since the damage is caused by a combination of weaknesses. This aspect complicates the diagnosis considerably when it is a matter of assigning responsibilities. The more difficult the conditions of use of soil appear to be, the more careful and rigorous the project’s design and implementation must therefore be. In addition to emphasizing the important of surface sewerage and drainage as a “trigger” or aggravating cause, it should also be borne in mind that many flaws take long periods of time to emerge. Thus, a non-compacted embankment which has not been used by transport and construction vehicles will show its vicissitudes in a matter of weeks or perhaps a few months after completion. However, an embankment which has not been compacted by compaction machinery and has been used by transport and construction vehicles will only show its flaws after around 5 – 7 years. Likewise, drainage flaws may often be revealed, sometimes violently, after several years of operation, after an exceptional period of rainfall. It is most often impossible to carry out rehabilitation work on a poorly constructed embankment without demolishing it and rebuilding. The objective of reinforcement solutions is most frequently to slow down and reduce damage and defects, and rarely to eliminate them. All the evidence points to the care which must be taken when building such structures.


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March 2007


Annexes Acronyms used ADR European International Agreement for Road Transportation of Hazardous Goods (Accord européen relatif au transport international des marchandises Dangereuses par Route) AE

Commitment Document (Acte d’Engagement)

AEP AM

Drinking Water Supply (Alimentation en Eau Potable) Ministerial Order (Arrêté Ministériel)

AP

Prefectoral Order (Arrêté Préfectoral)

APA

Preliminary Motorway Project under Concession (Avant Projet Autoroutier concédé)

APOA

Preliminary Design for Structures (Avant Projet Ouvrage d’Art)

APOANC APS

Preliminary Design for Extraordinary/Non-Standard Structures (Avant Projet Ouvrage d’Art Non Courant) Overview / background summary (Avant-Projet Sommaire)

APSI

Overview / background summary, Route (Avant-Projet Sommaire d’Itinéraire)

APSM

Overview / background summary , Modifications (Avant-Projet Sommaire Modificatif)

APTCFH ARi

Earthworks Preliminary Design, Capping Layer, Hydraulics (Avant-Projet Terrassement, Couche de Forme, Hydraulique) Subformation Class i (Arase de classe i)

AVP

Preliminary Project (Avant-Projet)

BPU

Unit Prices Specification (Bordereau des Prix Unitaires)

BSDI

Specification for Monitoring of Industrial Waste (Bordereau de Suivi des Déchets Industriels)

CAP

Prior Acceptance Certificate (Certificat d’Acceptation Préalable)

CCAG CCAP

General Administrative Specifications (Cahier des Clauses Administratives Générales) Particular Administrative Specifications (Cahier des Clauses Administratives Particulières)

CCTP

Particular Technical Specifications (Cahier des Clauses Techniques Particulières)

CDC

District Quarries Commission (Commission Départementale des Carrières)

CDF

Capping Layer (Couche de Forme)

CDH

District Hygiene Council (Conseil Départemental d’Hygiène)

CE

Inquiry Commission (Commission d’Enquête)

CETE

Technical Engineering Center for Infrastructure (Center d’Etudes Techniques de l’Equipement)

CFG

French Geosynthetics Committee (Comité Français des Géosynthétiques)

CFTR

French Road Engineering Committee (Comité Français pour les Techniques Routières)

CLE CMP

Local Water Commission (Commission Locale de l’Eau) Procurement Contract Code (Code des Marchés Publics)

CRPF

Regional Forest Property Center (Center Régional de la Propriété Forestière)

CSP

Higher Fishing Council (Conseil Supérieur de la Pêche)

DCE

Tender Documents (Dossier de Consultation des Entreprises)

DDAF

DDE

District-Level Department for Agriculture and Forests (Direction Départementale de l’Agriculture et de la Forêt) District-Level Department for Sanitation and Social Affairs (Direction Départementale de l’Action Sanitaire et Sociale) District-Level Office for Infrastructure (Direction Départementale de l’Equipement)

DE

Estimate (Détail Estimatif)

DG

Final Account (Décompte Général)

DIB

Ordinary Industrial Waste (Déchet Industriel Banal)

DDASS


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March 2007


DICT DIREN

Declaration of Intent to Commence Work (Déclaration d’Intention de Commencement des Travaux) Region-level Office for the Environment (DIrection Régionale de l’Environnement)

DIS

Special Industrial Waste (Déchet Industriel Spécial)

DOE

Documents Conforming to Execution (Documents Conformes à l’Exécution)

DPE

Water Policing Dossier (Dossier de Police des Eaux)

DPF

Public Rivers Sector (Domaine Public Fluvial)

DPM

Public Maritime Sector (Domaine Public Maritime)

DRAC DRIRE

Region-level Office for Cultural Affairs (Direction Régionale des Affaires Culturelles) Region-level Office for Industry, Research and the Environment (Direction Régionale de l’Industrie, de la Recherche et de l’Environnement)

DUP DVA

Acknowledgement of Public Interest (Déclaration d’Utilité Publique) Cross-town Roads Dossier (Dossier de Voirie d’Agglomération)

DVAAPS EBC

Different Development Variants on Overview / background summary (Différentes Variantes d’Aménagement à l’Avant-Projet Sommaire) Classified Wooded Space (Espace Boisé Classé)

EDF

Electricité De France

EP

Preliminary Study (Etude Préliminaire)

EPAPA

Preliminary Study for Preliminary Motorway Project (Etude Préliminaire à l’Avant-Projet Autoroutier) Preliminary Study for Structures (Etude Préliminaire des Ouvrages d’Art)

EPOA EPOANC FNTP ICPE

Preliminary Study for Extraordinary Structures (Etude Préliminaire des Ouvrages d’Art Non Courants) National Public Works Federation (Fédération Nationale des Travaux Publics)

IOTA

Classified Facility for Protection of the Environment (Installation Classée pour la Protection de l’Environnement) Facilities, Structures, Work or Activities (Installations, Ouvrages, Travaux ou Activités)

IMEC

Central Level Mixed Instruction (Instruction Mixte à l’Echelon Central)

LCPC

Central Public Works Research Laboratory (Laboratoire Central des Ponts et Chaussées)

LOTI

Law for Orientation on Internal Transport (Loi d’Orientation sur les Transports Intérieurs)

LRPC

Regional Public Works Research Laboratory (Laboratoire Régional des Ponts et Chaussées)

MEDD

MES

Ministry for Ecology and Sustainable Development (Ministère de l’Ecologie et du Développement Durable (formerly MATE) Ministry for Regional Development and the Environment (Ministère de l’Aménagement du Territoire et de l’Environnement) Ministry for Infrastructure, Housing and Transport (Ministère de l’Equipement du Logement et des Transports) Material in Suspension (Matières En Suspension)

MISE

Water Inter-services Mission (Mission Inter-Services de l’Eau)

MOe

Construction Manager (Maîtrise d’œuvre)

MOu

Project Owner (Maîtrise d’Ouvrage)

NOE

Environmental Organization Note (Note d’Organisation Environnementale)

OA

Structures (Ouvrages d’Art)

OH

Hydraulic Structure (Ouvrage Hydraulique)

ONF OS

National Forestry Office (Office National des Forêts) Service Order (Ordre de Service)

PA

Awarding Authority (Pouvoir Adjudicateur)

PAE

Environmental Assurance Plan (Plan d’Assurance Environnement)

MATE MELT


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March 2007


PAQ

Quality Assurance Plan (Plan d’Assurance Qualité)

PE

Water Policing (Police de l’Eau)

PFi

Class i Platform (Plate Forme de classe i)

PGCS

General Safety Coordination Plan (Plan Général de Coordination Sécurité)

PLU SRU

Local Planning Scheme (Plan Local d’Urbanisme (replacing Land Occupation Plans following the Urban Renovation and Solidarity Law of December 2000)

PPR

POS

Plan for Prevention of Foreseeable Natural Risks (Plan de Prévention des Risques naturels prévisibles) Special Safety and Health Protection Plan (Plan Particulier pour la Sécurité et la Protection de la Santé) Land Occupation Plan (PLU as of December 2000)

PRO

Project (Projet)

PSIC

Community Interest Site Proposition (Proposition de Site d’Intérêt Communautaire - Natura 2000)

PST

Upper parts of earthworks (Partie Supérieure des Terrassements)

PV RC

Report (Procès Verbal) Rules for Tendering (Règlement de Consultation)

RC/A

Office for Supervision of Motorway Concessionary Companies (Mission de Contrôle des sociétés concessionnaires d’Autoroutes)

RNDE RPC

National Water Data Network (Réseau National de Données sur l’Eau) Special Rules for Tendering (Règlement Particulier de Consultation)

SAGE

Water Management and Development Plan (Schéma d’Aménagement et de Gestion de l’Eau)

SAPRR

Société des Autoroutes Paris-Rhin-Rhône

SCOT

Territorial Coherence Diagram (Schéma de COhérence Territoriale)

SDAGE

Water Management and Development Master Plan (Schéma Directeur d’Aménagement et de Gestion de l’Eau)

SDVP SEBTP

District-level Fish Plan (Schéma Départemental de Vocation Piscicole) Société d’Edition du Bâtiment et des Travaux Publics

Sétra

Service d’Études Techniques des Routes et Autoroutes

SMO

Project Management Syndicate (Syndicat de Maîtrise d’Ouvrage)

SN

Navigation Service (Service Navigation)

SOGED

SRU

Organizational Diagram for Waste Management and Disposal (Schéma Organisationnel de Gestion et d’Elimination des Déchets) Organizational Diagram for Environmental Assurance Plan (Schéma d’Organisation du Plan d’Assurance Environnement) Organizational Diagram for Quality Assurance Plan (Schéma d’Organisationnel du Plan d’Assurance Qualité) Urban Renovation and Solidarity (Solidarité et Rénovation Urbaine)

TN

Natural Ground (Terrain Naturel)

TV

Topsoil (Terre Végétale)

USIRF

Union des Syndicats de l’Industrie Routière Française

W

Water Content (Teneur en eau)

PPSPS

SOPAE SOPAQ

ZICO

Bird Conservation Area (Zone d’Importance pour la Conservation des Oiseaux)

ZPS

Special Protection Area (Zone de Protection Spéciale)

ZNIEFF

Natural Ecology/Fauna/Flora area (Zone Naturelle d’Intérêt Ecologique, Faunistique ou Floristique)

ZSC

Special Conservation Area (Zone Spéciale de Conservation)


– 188 –

March 2007


Bibliography Guides, notes and recommendations [1] Catalog of type structures for new roads. State highway network - Sétra/LCPC, December 1998 - Ref. D9828 [2]

New highways with little traffic. Design manual - Sétra/LCPC, July 1981 - Ref. D8112

[3] Detection of underground cavities using geophysical methods – Practical Guide - co-publication, LCPC / PN Criterre, 1977 [4]

Maintenance of green roadside ancillaries. Practical Guide - Sétra, February 2004 - Ref. 0406

[5] Development of main roads (excluding motorways and two-lane expressways). Technical Guide - Sétra, August 1994 - Ref. B9413 [6]

Command and control of geotechnical investigation of alignments. Technical Guide - LCPC, January 2001

[7]

Design and sizing of road structures. Technical Guide - Sétra, December 1994 - Ref. D9511

[8] Study and construction of embankments/fills on compressible soils. Technical Guide - LCPC/Sétra, November 2000 - Ref. D0034 [9] Organization of quality assurance in earthworks. Technical Guide - LCPC/Sétra, January 2000 - Ref. D9923 [10] Creation of embankments/fills and capping layers (GTR Technical Guide to Embankments & Fills). Fasc. I and II - Sétra/LCPC, September 1992 - Ref. D9233 [11] Blasting earthworks in roadwork sites. Technical Guide - CFTR - Sétra, January 2002 - Ref. D0126 [12] Embankment work on trenches and road reworking (GTT Technical Guide to Earthworks) - LCPC/Sétra, May 1994 - Ref. D944 [13] Treatment of soils containing lime and/or hydraulic binders. Application to creation of embankments/fills and capping layers. Technical Guide - Sétra/LCPC, January 2000 - Ref. D9924 [14] Technical guide to use of soils to construct green roadside ancillaries. Preliminary studies. Study report Sétra, May 2000 [15] Management of waste from road construction and operation. Information note No. 63 – Economics, environment, design - Sétra, April 2000 - Ref. B0011 [16] Repeated heat treatment of bituminous materials. Information note No. 98 – Ancillary Roadways - Sétra, April 1997 - Ref. D9725 [17] Weather conditions and earthworks. Recommendation for preparation of the project, drawing up the contract, execution and monitoring of work - Sétra/LCPC, June 1986 - Ref. D8629 [18] Recommendations for the Design and Execution of Road Embankments & Fills - AIPCR, 1999 [19] Earthworks – Assistance in drawing up CCTP Particular Technical Specifications – Methodological Guide - Sétra, October 2006 - Ref. 0646W [20] Use of expanded polystyrene in road construction - Technical Guide - Sétra, September 2006 - Ref. 0622 [21] Road drainage - Technical Guide - Sétra, September 2006 - Ref. 0605 [22] Ordinary technical clauses concerning metal ducts - Technical Guide - Sétra, November 1982 - Ref. F8218 [23] Walls – Retaining walls - IQOA - Methodological Guide - Sétra, March 2005 - Ref. 0507 [24] Road sewerage - Technical Guide - Sétra, October 2006 - Ref. 0632 [25] Structures in reinforced earth - Recommendations and rules - LCPC - Sétra, July 1991- Ref. F7910 [26] Le Pneusol (support – distribution of stresses – Information note No. 47 - Sétra, January 1989 [27] Ultra-light embankments/fills on compressible soils – Information note No. 54 - Sétra, February 1990 [28] Support and embankments/fills in Texsol - E. Leflaive and M. Panet, Coll; Innovation routière, Paris 1995 Collection « Les outils” – Sétra

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March 2007


[29] Site and building waste. Guide to professional building usage - Fédération Nationale du Bâtiment (FNB) January 1995

Regulations [30] Law No. 75-633 of 15 July 1975 concerning elimination of waste and recovery of materials. [31] Law No. 76-663 of 19 July 1976 concerning classified facilities for protection of the environment. [32] Law No. 92-646 of 13 July 1992 in completion and modification of the two laws of 1975 and 1976. [33] Law No. 95-101 of 2 February 1995 (“Barnier Law”) concerning reinforcement for protection of the environment. [34] European Council Directive 75/442/CEE modified by directives 91/156/CEE of 18/03/91 and 96/350/CE on waste (JOCE L 194 of 25/07/1995) [35] European Council Directive 1999/31/CE of 26 April 1999 concerning dumping of waste. [36] Commission Decision 2000/532/CE of 16 January 2001 concerning the European waste list. [37] Environmental Code, Book V, Section IV: Waste – Chapter 1: Elimination of waste and recovery of materials. [38] Environmental Code, Book V, Section I concerning classified facilities for protection of the environment [39] Joint circular Ministry for Regional Development and the Environment / Ministry for Infrastructure, Housing and Transport of 15 February 2000 on planning for waste from building sites and public works. [40] Decree No. 94-609 of 13 July 1994 concerning non-household packaging waste. [41] Decree No. 97-517 of 15 May 1997 concerning the classification of hazardous waste. [42] Decree No. 98-679 of 30 July 1998 concerning the transportation of waste by road. [43] Circular No. 2001-39 of 18 June 2001 concerning waste management on the state highway network METL/MATE (BO No. 2001-13) [44] Circular of 28 April 1998, Ministry for Regional Development and the Environment, concerning the implementation and evolution of district-level plans for elimination of household and assimilated waste (not published in the Official Journal) [45] Regulation NF P 11-300 - September 1992 - Execution of earthworks - Classification of materials to be used in the construction of embankments/fills and capping layers for road infrastructures [46] Regulation NF P 11-301 - December 1994 - Execution of earthworks - Terminology [47] NF P 94-102-1 - July 2001 - Soils: investigation and tests – Soil treated with hydraulic binder and possibly lime, for use on capping layer - Part 1: Definition - Composition - Classification [48] NF P 94-102-2 - July 2001 - Soils: investigation and tests – Soil treated with hydraulic binder and possibly lime, for use on capping layer - Part 2: methodology for lab formulation studies. [49] Section 2 – General earthworks – CCTG General Technical Specifications - March 2003 (Special Section, BO No. 2003-2) [50] Sections 35 – Landscape development. Open-air sports and leisure areas - CCTG General Technical Specifications - April 1999 (Special Section BO No. 99-6) [51] Mining Code


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Other documents [52] Article 10 of the Water Act No. 92-3 of 3 January 1992 and Application Decree 29/03/1993 concerning nomenclature of operations subject to authorization or declaration [53] Notice of 11 November 1997 concerning nomenclature of waste (Official Journal of 11/11/1997) [54] Stability of slopes – Volume 1: Natural slopes, Volume 2: Cuts and embankments/fills – Special Bulletin III, Public Works Research Laboratories - March 1976 [55] Hydraulics of soils - Special Bulletin V, Public Works Research Laboratories – April 1970 [56] Natural Risks – Liaison Bulletin, Public Works Research Laboratories No. 150–151 – July - October 1987 [57] Compaction with low water content in soils and materials for earthworks and roads - ISTED – October 1986 [58] Applied geophysics: Code of Good Practices - Édition Union Française des Géologues, Paris 1992. [59] Guide to building site waste - Coll.: Knowledge for action - ADEME, 1998. [60] Plans for Prevention of Foreseeable Natural Risks – General Guide - La documentation Française, 1997 [61] Plans for Prevention of Natural Risks. Risks of movements in ground. Methodological Guide MATE/MELT - La documentation Française, 1999 [62] Stability of slopes on cuts and embankments/fills – Special issue, LPC - LCPC, December 1976 [63] Site by-products and surpluses, proposals and solutions - FNTP, 1999 [64] Soil improvement by vertical rigid inclusions – Application to construction of embankments/fills on mediocre soils - O. Combarieu – Studies and research by the Public Works Research Laboratories, geotechnical series GT-26 - LCPC, December 1987.


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The purpose of the guide to “Design and execution of earthworks” is to assist and advise the Construction Manager in the course of the project up to execution of earthworks. It consists of 3 independent fascicules: • fascicule 1: studies and execution of work; • fascicule 2: organization of checks; • fascicule 3: test methods. This fascicule 1 “Studies and execution of work” is composed of six chapters. The first describes the recommended longitudinal section techniques. The second consists of technical dossiers on earthworks technology. The third describes earthwork techniques which are not currently explained by technical guides. The fourth provides specific examples. The fifth examines the problem of variants. The sixth provides a summary of pathologies observed.

This document is available and can be downloaded on Sétra website: http://www.setra.equipement.gouv.fr Cover - Photographers: A. Delfaut (D REIF - L RPC ), Y. Aubert (Entreprise G TM Terrassements), Y. Deniel (D DE 28), C. Drouaux (Sétra), G. Lacassy (C ETE du Sud-Ouest - L RPC ), E. Mazière (Entreprise G TM Terrassements), P. Pettier (Scétauroute), P. Rossi (Entreprise Razel), N. Travers (D DE 50). Sétra authorization is required for reproduction of this document (all or even part) © 2007 Sétra - Reference: 0748-1A - ISRN: EQ-SETRA--07-ED44--FR+ENG

Sétra belongs to the scientific and technical network of the French Public Works Ministry (RST)

SETRA_Design and execution of earthworks_1 _2007+++++++++++++++++

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