Sprayed Concrete

British Standard I S B ) c ( , y p o C d e l l o r t n o c n U , 3 0 0 2 r e b o t c O 9 0 , h t a B f o y t i s r e v i n U , y r a r b i L h t a B f o y t i s r e v i n U : y p o C d e s n e c i L

A single copy of this British Standard is licensed to University of Bath Library

09 October 2003

This is an uncontrolled copy. Ensure use of the most current version of this document by searching British Standards Online at bsonline.techindex.co.uk

Form 36 Version 6.1

Draft for Public Comment

DPC: 02/104236 DC

Head Office 389 Chiswick High Road London W4 4AL

Date: 25 June 2002 Origin: European European

Telephone: +44(0)20 8996 9000 Fax: +44(0)20 8996 7001

Project no.: 2002/01893

Latest date for receipt of comments: 2002.09.30

I S B ) c ( , y p o C d e l l o r t n o c n U , 3 0 0 2 r e b o t c O 9 0 , h t a B f o y t i s r e v i n U , y r a r b i L h t a B f o y t i s r e v i n U : y p o C d e s n e c i L

Respons Responsible ible committe committee: e:

B/517/1 B/517/1 Concre Concrete te Productio Production n And And Testing Testing

Intereste Interested d committees committees::

B/2; B/11; CB/1; CB/1; B/517; B/517; B/525/2 B/525/2

Title: Title:

Draft EN 144 14487: 87: PART PART 1 Sprayed Sprayed Con Concrete crete Part 1: Defintitions, Specifications and Conformity

Supersession information: If you are aware of a current national standard which may be affected, please notify the secretary (contact details below).

WARNING: THIS IS A DRAFT AND MUST NOT BE REGARDED OR USED AS A BRITISH STANDARD. THIS DRAFT IS NOT CURRENT BEYOND 2002.09.30. This draft is issued to allow comments from interested parties; all comments will be given consideration prior to publication. No acknowledgement will normally be sent. See overleaf for information on commenting. No copying is allowed, in any form, without prior written permission from BSI except as permitted under the Copyright, Designs and Patent Act 1988 or for circulation within within a nominating organization organization for briefing purposes. purposes. Electronic Electronic circulation is limited to dissemination by e-mail within such an organization by committee members. Further copies of this draft may be purchased from BSI Customer Services, Tel: +44(0) 20 8996 9001 or email [email protected] . British, International and foreign standards are also available from BSI Customer Services. British Standards on CD or Online are available from British Standards Publishing Sales Limited. Tel: 01344 404409 or email [email protected] . Information on the co-operating organizations represented on the committees referenced above may be obtained from the responsible committee secretary. Cross-references The British Standards which implement International or European publications referred to in this draft may be found via the British Standards Online Service on the BSI web site http://www.bsi-global.com http://www.bsi-global.com..

Responsible Committee Secretary Secretary:: Miss A Attra (BSI)

Direct Direct tel: tel: E-mail: E-mail:

020 020 8996 8996 7603 7603

anita.attr anita.attra@bs a@bsi-glo i-global bal.com .com

a

Form 36 Version 6.1

Draft for Public Comment

DPC: 02/104236 DC

Head Office 389 Chiswick High Road London W4 4AL

Date: 25 June 2002 Origin: European European

Telephone: +44(0)20 8996 9000 Fax: +44(0)20 8996 7001

Project no.: 2002/01893

Latest date for receipt of comments: 2002.09.30


Respons Responsible ible committe committee: e:

B/517/1 B/517/1 Concre Concrete te Productio Production n And And Testing Testing

Intereste Interested d committees committees::

B/2; B/11; CB/1; CB/1; B/517; B/517; B/525/2 B/525/2

Title: Title:

Draft EN 144 14487: 87: PART PART 1 Sprayed Sprayed Con Concrete crete Part 1: Defintitions, Specifications and Conformity

Supersession information: If you are aware of a current national standard which may be affected, please notify the secretary (contact details below).

WARNING: THIS IS A DRAFT AND MUST NOT BE REGARDED OR USED AS A BRITISH STANDARD. THIS DRAFT IS NOT CURRENT BEYOND 2002.09.30. This draft is issued to allow comments from interested parties; all comments will be given consideration prior to publication. No acknowledgement will normally be sent. See overleaf for information on commenting. No copying is allowed, in any form, without prior written permission from BSI except as permitted under the Copyright, Designs and Patent Act 1988 or for circulation within within a nominating organization organization for briefing purposes. purposes. Electronic Electronic circulation is limited to dissemination by e-mail within such an organization by committee members. Further copies of this draft may be purchased from BSI Customer Services, Tel: +44(0) 20 8996 9001 or email [email protected] . British, International and foreign standards are also available from BSI Customer Services. British Standards on CD or Online are available from British Standards Publishing Sales Limited. Tel: 01344 404409 or email [email protected] . Information on the co-operating organizations represented on the committees referenced above may be obtained from the responsible committee secretary. Cross-references The British Standards which implement International or European publications referred to in this draft may be found via the British Standards Online Service on the BSI web site http://www.bsi-global.com http://www.bsi-global.com..

Responsible Committee Secretary Secretary:: Miss A Attra (BSI)

Direct Direct tel: tel: E-mail: E-mail:

020 020 8996 8996 7603 7603

anita.attr anita.attra@bs a@bsi-glo i-global bal.com .com

a

Introduction This draft standard is based based on European discussions in which the UK took an active part. Your comments comments on this draft are welcome and will assist in the preparation of of the consequent British Standard. If no comments are received received to the contrary, then the UK will approve this draft and implement implement it as a British Standard. Standard. Comment Comment is particularly welcome on national, legislative or similar deviations that may be necessary. Even if this draft standard is not approved by the UK, if it receives the necessary support in Europe, the UK will be obliged to publish the official English Language text unchanged as a British Standard and to withdraw any conflicting standard. UK Vote Please indicate whether you consider the UK should submit a negative (with reasons) or positive vote on this draft.


Submission The guidance given below is intended to ensure that all comments receive efficient and appropriate attention by the responsible BSI committee. Annotated drafts are not acceptable and will be rejected. All comments must be submitted, preferably electronically, to the Responsible Committee Secretary at the address given on the front cover. Comments should should be compatible with Version 6.0 or Version 97 of of Microsoft® Word for Windows™, if possible; otherwise comments in ASCII text format are acceptable. Any comments not submitted electronically should still adhere to these format requirements. All comments submitted should should be presented as given in the example below. below. Further information information on submitting comments and how to obtain a blank electronic version of a comment form are available from the BSI web site at: http://www.bsi-global.com/Stan http://www.bsi-g lobal.com/Standards+De dards+Development/Drafts/ind velopment/Drafts/index.xalter ex.xalter

D ate

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Amend to read ‘... so that the mains connector to which no connection ...’

(General/ technical/editorial)

3.1

1st d efi ni ti on

Editori al

D ef efiniti on is amb igu ous and needs clarifying.

6.4

§2

Technic al

T he us e of t he U V Delete reference to UV photometer as an alternative alternative photometer. cannot be supported as serious problems have been encountered in its use in the UK.

OBSE RV RV AT ATIONS OF THE SECRETARIAT

Microsoft and MS-DOS are registered trademarks, and Windows is a trademark of Microsoft Corporation.

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EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM

DRAFT prEN 14487-1 June 2002

ICS

English version

Sprayed concrete - Part 1: Definitions, specifications and conformity I S B ) c ( , y p o C d e l l o r t n o c n U , 3 0 0 2 r e b o t c O 9 0 , h t a B f o y t i s r e v i n U , y r a r b i L h t a B f o y t i s r e v i n U : y p o C d e s n e c i L

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee CEN/TC 104. If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. Warning : This document is not a European Standard. It

shall not be referred to as a European Standard.

is distributed for review and comments. It is subject to change without notice and

EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: rue de Stassart, 36

© 2002 CEN

All rights of exploitation in in any form and by any means reserved worldwide for CEN national Members.

B-1050 Brussels Brussels

Ref. No. prEN 14487-1:2002 E

prEN 14487-1:2002 (E)

Contents Foreword......................................................................................................................................................................3 Introduction .................................................................................................................................................................4 1

Scope ..............................................................................................................................................................4

2

Normative references ....................................................................................................................................5

3 I 3.1 S3.2 B ) 3.3 c ( 3.4 , y 3.5 p o 3.6 C3.7

d e l l 4 o r 4.1 t n 4.2 o 4.3 c n 4.4 U , 4.5 3 4.6 0 0 2 5 r e 5.1 b 5.2 o t c 5.3 O5.4 9 5.5 0 , h t 6 a 6.1 B f 6.2 o 6.3 y t i 7 s r e 7.1 v i n 7.2 U7.3 , 7.4 y r 7.5 a r b i Annex L h t Annex a B f o y t i s r e v i n U : y p o C d e s n e c i L 2

Terms and definitions....................................................................................................................................6 Mix Component ..............................................................................................................................................6 Product............................................................................................................................................................6 Process ...........................................................................................................................................................7 Properties .......................................................................................................................................................7 Execution........................................................................................................................................................8 Operative.........................................................................................................................................................8 Test/Inspection...............................................................................................................................................8 Classification and designation .....................................................................................................................9 Consistence of wet mix .................................................................................................................................9 Exposure classes...........................................................................................................................................9 Young sprayed concrete ...............................................................................................................................9 Compressive strength .................................................................................................................................10 Flexural strength..........................................................................................................................................10 Fibre reinforced sprayed concrete.............................................................................................................10 Requirements for sprayed concrete ..........................................................................................................11 Requirements for constituent materials....................................................................................................11 Requirements for sprayed concrete composition....................................................................................12 Requirements on the basic mix..................................................................................................................14 Requirements on the fresh sprayed concrete ..........................................................................................14 Requirements on hardened sprayed concrete .........................................................................................14 Specification of sprayed concrete .............................................................................................................16 General..........................................................................................................................................................16 Data for specifying designed mixes ..........................................................................................................16 Data for specifying prescribed mix............................................................................................................17 Assessment of conformtity.........................................................................................................................17 General..........................................................................................................................................................17 Inspection classification .............................................................................................................................17 Preconstruction testing...............................................................................................................................18 Production control .......................................................................................................................................20 Conformity criteria.......................................................................................................................................24 A (informative) Guidelines for Definitions, Specification and Conformity for Sprayed concrete.........26 B (informative) General Guidelines for Steel Fibres for Sprayed Concrete ............................................34

prEN 14487-1:2002 (E)

Foreword This document (prEN 14487-1) has been prepared by Technical Committee CEN/TC 104, "Concrete and related products", the secretariat of which is held by DIN. This document is currently submitted to the CEN Enquiry. This standard has taken EN 206 as a basis, some clauses where re-stated because of their importance and some where modified to meet the specific requirements of sprayed concrete. I S B ) c ( , y p o C d e l l o r t n o c n U , 3 0 0 2 r e b o t c O 9 0 , h t a B f o y t i s r e v i n U , y r a r b i L h t a B f o y t i s r e v i n U : y p o C d e s n e c i L

This standard is only operable with product standards for constituent materials (ie. cement, aggregates, additions, admixtures and mixing water) and related test methods for sprayed concrete. These product standards and test method standards are under preparation by CEN but they will not be all available as European standards at the date of publication of this standard. For this reason, the latest date of withdrawal of national standards (dow) conflicting with this standard will be the date when all standards listed below, together with the related standards for test methods are available and implemented as European standards or ISO standards when appropriate or have the status required by this standard. EN 197-1, Cement — Composition, specifications and conformity criteria — Part 1: Comment cements. EN 12620, Aggregates for concrete including those for use in roads and pavements. EN 1008, Mixing water for concrete — Specifications and tests . EN 934-2, Admixtures for concrete, mortar and grout — Part 2: Concrete admixtures - Definitions and requirements. EN 934-5, Admixtures for concrete, mortar and grout — Part 5: Admixtures for sprayed concrete . EN 934-6, Admixtures for concrete, mortar and grout — Part 6: Sampling, conformity control and evaluation of conformity EN 450, Fly ash for concrete — Definitions, requirements and quality control . EN 13263, Silica fume for concrete — Definitions, requirements and quality control . EN 14487-2, Sprayed concrete — Part 2: Execution of Sprayed Concrete works . EN 14488 Series, Sprayed concrete — Test Methods.

3

prEN 14487-1:2002 (E)

Introduction This standard will be applied in Europe under different climatic and geographical conditions, different levels of protection and under different, well established, regional traditions and experience. Classes for concrete properties have been introduced to cover this situation. Where such general solutions were not possible, the relevant clauses contain permission for the application of EN 206 or other standards valid in place. This standard incorporates rules for the use of constituent materials that are covered by European standards. Other by-products of industrial processes, recycled materials etc. are in current use based on local experience. Until European specifications for these materials are available, this standard will not be provide rules for their use, but instead refers to the recommendations given in EN 206 to apply national standards or provisions valid in the place of use of the concrete. This standard defines tasks for the specifier, producer and user. For example, the specifier is responsible for the

I specification of concrete, clause 5 and 6 and the producer is responsible for conformity and production control, S Bclause 7. The user is responsible for placing the concrete in the structure. In practice there may be serveral ) different parties specifying requirements at various stages of the design and construction process eg. the client, the c ( , designer, the contractor, the concreting sub-contractor. Each is responsible for passing the specified requirements, y together with any additional requirements, to the next party in the chain until they reach the producer. In the terms p o of this standard, this final compilation is known as the "specification". C d e Annex B gives guidelines for steel fibres for sprayed concrete. These guidelines remain valid until superseded by a l l new EN standard on fibres for concrete. o r t n o Further explanations and guidance on the application of this standard are given in Annex A. c n U , 3 0 1 Scope 0 2 r This European Standard is applicable to sprayed concrete, to be used for repair and upgrading of structures, for e b new structures and for strengthening of ground. o t c OThis standard covers : 9 0 ,  Classification related to consistence of wet mix; h t a B  Environmental exposure classes; young, hardened and fibre reinforced concrete; f o y  Requirements for constituent materials; concrete composition and for basic mix; and for fresh and hardened t i s concrete and all types of fibre reinforced sprayed concrete. r e v i n  Specification for designed and prescribed mixes U , y r  Conformity a r b i The standard is applicable to wet mix as well as dry mix sprayed concrete. L h t The substrates to which sprayed concrete can be applied include: a B f o  ground (rock and soil) y t i s r  sprayed concrete e v i n  different types of formwork U : y  structural components constituted of concrete, masonry and steel p o C d  drainage materials e s n  insulating materials e c i L 4

prEN 14487-1:2002 (E)

Additional or different requirements may be needed for applications not within this standard, for instance-refractory.

2

Normative references

This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies. prEN 14487-1, Sprayed Concrete — Part 1: Definition, Specification and Conformity. I S B ) c ( , y p o C d e l l o r t n o c n U , 3 0 0 2 r e b o t c O 9 0 , h t a B f o y t i s r e v i n U , y r a r b i L h t a B f o y t i s r e v i n U : y p o C d e s n e c i L

prEN 14487-2, Sprayed Concrete — Part 2: Execution for Structures, Ground Strengthening, Repair and Upgrading. prEN 14488-1, Sprayed Concrete — Test Methods — Part 1: Sampling. prEN 14488-2, Sprayed Concrete — Test Methods — Part 2: Determination of compressive strength of young sprayed concrete. prEN 14488-3, Sprayed Concrete — Test Methods — Part 3: Determination of flexural and residual strengths of fibre reinforcement sprayed concrete. prEN 14488-4, Sprayed Concrete — Test Methods — Part 4: Determination of bond strength. prEN 14488-7, Sprayed Concrete — Test Methods — Part 7: Determination of fibre content. EN 197-1, Cement — Composition, specification and conformity criteria — Part 1: Common cements. EN 206-1:2000-12, Concrete — Part 1: Specification, performance, production and conformity. EN 934-2, Admixtures for concrete, mortar and grout — Part 2: Concrete admixtures - Definitions and requirements. EN 934-5, Admixtures for concrete, mortar and grout — Part 5: Admixtures for sprayed concrete . EN 934-6, Admixtures for concrete, mortar and grout — Part 6: Sampling, conformity control and evaluation of conformity prEN 1008:1997-05, Mixing water for concrete — Specification and tests. prEN 1504-3:2001-03, Products and systems for protection and repair of concrete structures — Definitions, requirements, quality control and evaluation of conformity — Part 3: Structural and non structural repair. EN 1542, Products and systems for the protection and repair of concrete structures – Test methods – Measurement of bond strength by pull-off EN 12350-2, Testing fresh concrete — Part 2: Slump test . EN 12350-5, Testing fresh concrete — Part 5: Flow table test. EN 12350-6, Testing fresh concrete — Part 6: Density of fresh concrete. EN 12390-5, Testing hardened concrete — Part 5: Determination of flexural strength. EN 12390-7, Testing hardened concrete — Part 7: Density of hardened concrete. EN 12390-8, Testing hardened concrete — Part 8: Depth of penetration of water under pressure. EN 12504-1, Testing concrete in structures — Part 1: Cored specimens, taking, examining and testing in compression. 5

prEN 14487-1:2002 (E)

prEN 12504-3:1999-12, Testing concrete in structures — Part 3: Determination of pull-out force prEN 12620:2000-03, Aggregates for concrete. prEN 13412:1998-11, Products and systems for the protection and repair of concrete structures — Test Methods — Determination of elastic modulus in compression. ENV 13670-1, Execution of concrete structures - Part 1: Common rules. ISO 758, Liquid chemical products for industrial use — Determination of density at 20 °C. EN ISO 7031, Resistance to water penetration. ISO 6784, Modulus of elasticity in compression. I SISO 4012:1978, Concrete; Determination of compressive strength of test specimens. B ) c ( , y 3 Terms and definitions p o CFor the purposes of this European Standard, the following terms and definitions apply. d e l l o r 3.1 Mix Component t n o c 3.1.1 n UFibres , are short, discrete lengths of steel, organic polymer, glass or carbon and sufficiently small to be dispersed in the 3 0 sprayed concrete. 0 2 r e 3.2 Product b o t c 3.2.1 OBasic mix 9 a concrete mix delivered ready-mixed or mixed on site intended to be fed into the spraying machine and 0 , transported to the nozzle. h t a B3.2.2 f o Dry mix y a basic mix with a maximum moisture content not exceeding 0,5 % to be used for the dry process. t i s r e 3.2.3 v i n Factory blended dry mix Ua manufactured dry mix delivered to site in bags or silos. , y r a r 3.2.4 b i Fibre reinforced sprayed concrete L a sprayed concrete, including reinforcing fibres to improve certain properties of concrete. h t a B3.2.5 f Rebound o y the part of material that, having been sprayed through the nozzle, does not adhere to the surface of application. t i s r e 3.2.6 v i n Reference sprayed concrete Usprayed concrete using site materials without accelerator for determining the changes in the mechanical properties : (e.g strength loss). y p o C3.2.7 d Sprayed concrete e s a basic mix projected pneumatically from a nozzle into place, to produce a dense homogenous mass compacted by n e its own momentum. c i L 6

prEN 14487-1:2002 (E)

3.2.8 Wet mix a basic mix to be used in the wet process. 3.2.9 Young sprayed concrete sprayed concrete up to an age of 24 hours.

3.3

Process

3.3.1 Curing measures to reduce harmful evaporation from concrete. I S B ) c ( , y p o C d e l l o r t n o c n U , 3 0 0 2 r e b o t c O 9 0 , h t a B f o y t i s r e v i n U , y r a r b i L h t a B f o y t i s r e v i n U : y p o C d e s n e c i L

3.3.2 Dense flow conveying the pump conveying of a wet mix to the nozzle, where it is pneumatically projected and compacted by adding highpressure air. Dense flow conveying can only be used in the wet process. 3.3.3 Dry process method of spraying a dry mix. (The necessary amount of additional water is added in the nozzle.) 3.3.4 Nozzle general term for the end of the conveying line, through which the mix is discharged. It consists of a mixing unit, into which – depending on the process – water, compressed air and/or admixtures are injected into the flow of the basic mix. 3.3.5 Thin flow conveying conveying of the basic mix through hoses or pipes in a continuous stream of high pressure air to the nozzle, where the force of the transportation is used to project and compact the mix. 3.3.6 Wet process method of spraying a wet mix with an established water/cement ratio.

3.4

Properties

3.4.1 Early development classes define the ranges of the early setting and early strength development upto 24 hours. 3.4.2 Aspect ratio of fibre ratio of length to diameter or equivalent diameter of the fibre. 3.4.3 Deformation level degree of deformation that the lining undergoes after spraying. 3.4.4 Equivalent diameter of fibre diameter of a circle with area equal to the cross-sectional area of a non-circular fibre. 3.4.5 First peak flexural strength the stress at the determined first peak load which fibre reinforced concrete withstands when subjected to a flexural test as specified in prEN 14488-3.

7

prEN 14487-1:2002 (E)

3.4.6 Ultimate flexural strength the stress corresponding to the maximum load which unreinforced or fibre reinforced concrete can withstand when subjected to a flexural test as specified in EN 12390-5 and prEN 14488-3. 3.4.7 Fresh sprayed concrete concrete prior to setting. 3.4.8 Residual strength is the calculated stress in fibre reinforced concrete corresponding to a load in the load-deflection curve recorded during the flexural test as defined in test prEN 14488-3. I 3.4.9 SShadow effect Bthe phenomena of a poorer concrete compaction or voidage on the rear side, of for example, a reinforcement bar, ) c which is being sprayed on from one side only. ( , y p 3.4.10 o COpen time d the time between mixing and latest possible spraying of the basic mix. It depends on type and quantity of cement, e l l moisture content for the dry mix and temperature. o r t n o 3.5 Execution c n U3.5.1 , 3 Repair 0 the replacement of inferior or deteriorated parts of concrete or masonry members. 0 2 r e 3.5.2 b o Substrate t c the surface to which the sprayed concrete is applied. O 9 3.5.3 0 , Surface improvement h t the use of layer of sprayed concrete in order to improve the durability or the appearance of the structure. a B f o 3.5.4 y Upgrading t i s r the placing of additional sprayed concrete – with or without reinforcement – in order to increase the loadbearing e capacity or the integrity of the structure. v i n U , 3.6 Operative y r a r 3.6.1 b i Nozzleman L the operator who controls and regulates the application of the sprayed concrete. h t a B f 3.7 Test/Inspection o y t i 3.7.1 s r Preliminary test for sprayed concrete e v test or tests to check how a sprayed concrete shall be composed in order to meet all the specified requirements in i n Uthe fresh and hardened state. : y p 3.7.2 o CPreconstruction test d test or tests performed with the proposed personnel, materials, equipment and spray method which the contractor e will carry out before the start of the spraying work to ensure the specified properties are met. s n e c i L 8

prEN 14487-1:2002 (E)

3.7.3 Inspection activities carried out in order to check that execution is in accordance with the project specification. 3.7.4 Inspection class defines the subjects to be inspected and the extent of inspection, with reference to three inspection classes. 3.7.5 Assessment of conformity systematic examination of the extent to which a production process and a product are capable of fulfilling special requirements.


4 4.1

Classification and designation Consistence of wet mix

The classification of consistence of fresh concrete in this standard is applicable for wet mixed concrete before being sprayed and consistence classes in EN 206-1 shall be applied.

4.2

Exposure classes

The limiting values for composition of concrete related to the exposure classes given in EN 206-1, apply for sprayed concrete with the following exceptions: 

Recommendation on minimum cement content does not apply to sprayed concrete



Recommendation on minimum air content is not applicable.

4.3

Young sprayed concrete

The young sprayed concrete shall be classified within the ranges of its significant early strength development. The recommended classification is based on the average range of the typical setting rate according to the chosen production process and requirements. When specified the strength development of the young sprayed concrete shall apply to the early strength classes J1, J2 or J3 according to figure 1. Early strength class J1 is defined in the field between the lines A and B, class J2 in the field between the lines B and C and class J3 above the line C. Early strength development shall be determined with penetration needle method according to test standard prEN 14488-2 and bolt driving method according to test standard prEN 14488-2.

9

prEN 14487-1:2002 (E)

I S B ) c ( , y p o C d e l l o r Figure 1 — Early strength classes of young sprayed concrete t n o Early compressive strength of young concrete up to 24 hours can be estimated by different indirect test methods in c NOTE n accordance with Table 1: U , 3 0 Table 1 — Range of strength of young concrete determined by different test methods 0 2 r Method Range of strength of young e b concrete (MPa) o t c prEN 14488-2 – Method 0,2–1,2 O A 9 0 , prEN 14488-2 – Method 3–16 h t B a B f prEN 12504-3:1999-12 > 10 o y t i s r e v 4.4 Compressive strength i n U , The compressive strength of sprayed concrete is classified according to EN 206-1. y r a r b i 4.5 Flexural strength L h t Shall be tested according to EN 12390-5 or prEN 14488-3 whichever is appropriate for comparative purposes. a B f o 4.6 Fibre reinforced sprayed concrete y t i s r Fibre reinforced sprayed concrete has additional and/or complementary properties, some of which are related to e residual strength and energy absorption capacity. Informative guidance to the classification prinicples are given in v i n Appendix B. Informative guidance to the classification principles are given in Appendix B U : y 4.6.1 Residual strength classes p o C Classification of residual strength is made by specification of a strength level at a certain deformation range d e according to Table 2 and determined in accordance with prEN 14488-3 and denoted by combination of the signs s n for the specified deformation range and strength level. e.g. Residual strength Class D2S2 means that the strength e must exceed 2 Mpa at 0,5, 1 and 2 mm deflection. c i L 10

prEN 14487-1:2002 (E)

Table 2 — Definitions of residual strength classes Deformation range

Strength level (Minimum strength, MPa)

Deflection mm


5

D1

0,5–1

D2

0,5–2

D3

0,5–4

S1

S2

S3

S4

1

2

3

4

Requirements for sprayed concrete

5.1

Requirements for constituent materials

5.1.1

Suitability for constituent materials

Constituent materials shall not contain harmful ingredients in such quantities as may be detrimental to the durability of the concrete, or cause corrosion of the reinforcement. Only constituent materials with established suitability shall be used. Suitability of a constituent material is established when it conforms to a European Standard. Alternatively, where either the European Standard does not cover the particular material or its intended performance, or the material deviates from the requirements of an existing European Standard, the establishment of suitability may result from: 

a European Technical Approval which refers specifically to the use of the material in sprayed concrete conforming to this standard.



from the relevant national standards or provisions valid in the place of use of the sprayed concrete, which refers specifically to the use of the material in sprayed concrete conforming to this standard.

5.1.2

Constituent materials

Requirements for constituent materials are given in table 4.

11

prEN 14487-1:2002 (E)

Table 3 — Requirements for constituent materials Constituent material

Requirements

Cement

The suitability is established for cement conforming to EN 197-1

Aggregates

The suitability is established for aggregate conforming to prEN 12620:2000-03.

Mixing water

Mixing water shall conform to prEN 1008:1997-05.

Admixtures

Admixtures shall conform to EN 934-2 and/or prEN 934-5:1998-11 and EN 934-6

Additions (including mineral fillers and pigments)

Additions shall comply to requirements as specified in EN 206-1

Polymers modified sprayed

Polymer modified sprayed concrete used for repair shall comply with

I prEN 1504-3. S concrete B Steel fibres for reinforcement shall meet the requirements of Annex A ) Fibres c ( (Normative). , y Other fibres shall conform to general clause 5.1. p o C d e l l 5.2 Requirements for sprayed concrete composition o r t n o c 5.2.1 General n U , The concrete mix proportions shall be selected to satisfy all the performance criteria for fresh and hardened 3 0 concrete including consistence (wet mix), density, strength, durability, protection of embedded steel against 0 corrosion and taking into account the current process technique and quantity of rebound and dust when executing 2 r the spraying works. e b o The requirements for concrete composition and properties related to exposure classes depend on the intended t c Odesign life of the sprayed concrete structure and in conformity with EN 206-1. 9 0 Values for the composition of the concrete refer to the concrete after spraying and have to take into account the , h t influence of water addition by the spraying process as well as the effect of rebound. a B f The achievement of the design life depends on: o y t i  the concrete being sprayed and cured in accordance with ENV 13670-1. s r e v i  the sprayed concrete having an adequate cover to reinforcement or required extra thickness, in case of steel n fibre reinforcement, the cover requirement does not apply. U , y r  the sprayed concrete being used in the environment for which the particular limiting values apply; a r b i L  the anticipated maintenance without major repair. h t a B5.2.2 Concrete composition f o y t i s r e v i n U : y p o C d e s n e c i L 12

prEN 14487-1:2002 (E)

Table 4 — Requirement on concrete composition Component Use of cement

Requirement and Test Methods The type of cement shall be specifi ed, taking into account the influence of cu rrent temperature and heat evaluation on required workability time, the requirement on strength development and final strength as well as the current curing conditions. If required, it must be c hecked by means of an appropriate method. For permanent structures, the environmental conditions to which the sprayed concrete is exposed must be regarded according to EN 206-1:2000-12 clause 5.3.1.as well as precautions regarding resistance to alkali-silica reactions according to EN 206-1:2000-12 clause 5.2.3.4


Use of aggregates

Precautions regarding resistance to alkali-silica reactions according to EN 206-1:2000-12 clause 5.2.3.4 shall be applied.

Use of admixtures

Limitations for the use of admixtures set out in EN 934-2 and prEN 934- 5:1998-11 shall not be exceeded.

Use of additions

The use of additions for permanent structures shal l conform to clause EN 206-1:2000-12 clause 5.2.5

Chloride content

The chloride content of a sprayed concrete for permanent structure shall not exceed the values given in EN 206-1:2000-12 Table 10. For steel fibre reinforced sprayed concrete, values for steel reinforcement apply.

Water/cement ratio

For permanent structures, the environmental conditions to which the sprayed concrete is exposed must be regarded according to EN 206-1:2000-12, clause 5.3 Where water/cement ratio of a wet mix is specified, it shall be calculated according to EN 2061:2000-12, 5.4.2.

For fibre reinforced concrete Use of fibres

The use of steel fibres shall comply to Annex A, other types of fibres shall comply to clause 5.1 of this standard. Fibres shall be added in such a way that a homogenous distribution is obtained.

13

prEN 14487-1:2002 (E)

5.3

Requirements on the basic mix Table 5 — Requirements of the basic mix Property

Consistence of basic mix

Requirement and Test Methods The concrete consistency required for spraying depends on the type of conveyance and the application procedure. For sampling and determination of consistency of the basic wet mix sprayed concrete, EN 206-1 applies.

Temperature

The temperature of the basic mix before applying shall be between 5 °C and 30 °C in order to maintain the workability conditions and avoid adverse set effects.

I S B ) 5.4 Requirements on the fresh sprayed concrete c ( , y Table 6 — Requirements of the fresh concrete p o C Property Requirement and Test Methods d e l l Density If specified, the density shall be determined in accordance with EN 12350-6 o r t n Fore fibre reinforced sprayed concrete o c n U , 3 5.5 Requirements on hardened sprayed concrete 0 0 2 r e b o t c O 9 0 , h t a B f o y t i s r e v i n U , y r a r b i L h t a B f o y t i s r e v i n U : y p o C d e s n e c i L 14

prEN 14487-1:2002 (E)

Table 7 — Requirements of hardened concrete Property


Requirement and Test Methods

Young sprayed concrete

If specified an estimate of the early compressive strength can be determined in accordance with prEN 14488-2, alternatively the early strength can be determined from a pull-out test in accordance with prEN 12504-3:1999-12 for non fibre reinforced concrete.

Compressive strength

The compressive strength of sprayed concrete is expressed and defined according to EN 206-1. The strength shall be determined from tests carried out at 28 days in accordance with ISO 4012:1978 on drilled cores, taken from the sprayed concrete structure according to EN 12504-1, or from sprayed panels according to prEN 14488-1. Their minimum diameter shall be 50 mm and the height/diameter ratio shall be either 1.0 or 2.0, specimen shall be tested in accordance with EN 12504-1. NOTE

length/diameter ratio:

–

2.0 if the strength result is to be compared to cylinder strength

–

1.0 if the strength result is to be compared to cube strength.

Density

If specified, the density of hardened concrete shall be determined in accordance with EN 12390-7.

Modulus of elasticity

If specified, the modulus of elasticity in compression shall be determined in accordance with ISO 6784, except in repair application where prEN 13412:1998-11. Shall apply.

Flexural strength

If specified, the flexural strength shall be determined in accordance with prEN 12390-5 for plain sprayed concrete unless it is to be compared to fibre reinforced sprayed concrete when prEN 14488-Part 3 shall be used.

Resistance to water penetration

If water resistant sprayed concrete is specified, the resistance to water penetration shall be determined in accordance with EN 12390-8. The depth of an insitu sample may be reduced where the layer thickness is less than 150 mm. The depth shall be sufficient to ensure that complete penetration does not occur. In addition the direction of water penetration and the method of surface preparation shall be specified. The maximum value of penetration shall be 50 mm. The test is normally performed at 28 days.

Frost resistance

If specified, the frost resistance of sprayed concrete subjected to freezing and thawing shall be determined in accordance with prEN 14488-8

Bond strength to substrate

If specified, the bond strength shall be determined for repair materials in accordance with EN 1542 with the exception of mould size which shall not be smaller than 500 mm × 500 mm to provide a border of at least 100 mm in order to exclude defective material in the edges of the specimens. Surface finish shall either be trowelled when wet or ground when hardened otherwise it shall be on drilled cores in accordance with prEN 14488-4.

For fibre reinforced sprayed concrete First peak flexural strength

If the first peak flexural strength of fibre reinforced concrete is specified, the first peak strength shall be expressed as the average value of the strength at the moment of first peak determined on three samples in accordance with prEN 144883. The test shall normally be performed at 28 days.

Ultimate flexural strength If specified, the flexural strength of sprayed concrete shall be expressed as f fl when determined according to prEN 14488-3. Unless otherwise required tests shall normally be performed at 28 days Residual strength

If the residual strength class of fibre reinforced concrete is specified, it shall be done for a specified deformation level. The stress-deflection curve shall be determined on three samples in accordance with prEN 14488-3. The test is normally done at 28 days.

15

prEN 14487-1:2002 (E)

6 6.1

Specification of sprayed concrete General

Sprayed concrete shall be specified either as a designed mix referring to classification given in clause 4 and requirements given in clause 5, or as prescribed mix by prescribing the composition on the basis of results of initial tests or information obtained from long term experiences with comparable sprayed concrete. Where inspection classes 2 and 3 are specified only designed mixes shall be used. Where class 1 applies, prescribed mix may be used. Basic data for sprayed concrete shall be indicated in all cases and additional data shall be indicated when required.

6.2

Data for specifying designed mixes

I S6.2.1 Basic data B ) c (  Compressive strength class , y p o  Exposure class C d e  Maximum chloride content l l o r t In the case of fibre reinforced concrete n o c n  residual strength U , 3 0 6.2.2 Additional data 0 2 r The concrete specifications may also contain additional requirements such as: e b o t c  minimum cement content related to exposure class O 9  special requirements for cement properties (e.g. sulphate resistant cement) 0 , h t  maximum water/cement ratio related to exposure classes a B f  early strength development o y t i s r  maximum strength e v i n  resistance to water penetration U , y r  water absorption a r b i  bond to substrate L h t a  frost resistance B f o  modulus of elasticity y t i s r In the case of fibre reinforced concrete e v i n  first peak flexural strength U : y p  ultimate flexural strength o C d e s n e c i L 16

prEN 14487-1:2002 (E)

6.3

Data for specifying prescribed mix

6.3.1

Basic data

The prescribed mix shall be specified by the following basic data:




cement type and content



strength class



water/cement ratio



type of aggregate and limitations for grading



type and quantity of admixtures



type and quantities of additions



sources of all concrete constituents when admixture or additions are used

In the case of fibre reinforced concrete 

fibre type and content

6.3.2

Additional Data



additional requirements for aggregate



special requirements regarding the temperature of the basic mix for wet mix sprayed



concrete or dry mix sprayed concrete.

7

Assessment of conformtity

7.1

General

Conformity control comprises the combination of actions and decisions to be taken in accordance with conformity rules adopted in advance to check the conformity of the sprayed concrete with the specifications. Conformity shall be assessed by preconstruction control as well as test during execution and be applied in accordance with the applicable inspection classification. Production control includes process control and control of sprayed concrete The conformity or non-conformity is judged against the conformity criteria and is valid for preconstruction tests as well as for production tests. Conformity leads to acceptance while non-conformity shall lead to corrective action. NOTE If the results of conformity tests do not fulfil requirements, supplementary testing according to EN 12504-1 on cores taken from the structure may be required or a combination of tests on cores and non-destructive tests on the structure e g according to EN 12504-2.

7.2

Inspection classification

For conformity control of sprayed concrete the following inspection classes have been established. 

Inspection class 1



Inspection class 2



Inspection class 3 17

prEN 14487-1:2002 (E)

The choice of class shall be based on the characteristics of the project including degree of risk and required design life. The informative Annex A gives guidance for selection of inspection classes.

7.3

Preconstruction testing

Preconstruction test shall be performed according to Table 8 unless otherwise specified in production control system (Producer's production control manual). It shall be demonstrated that the requirements can be met before start of execution. The preconstruction tests shall be performed with the same personnel, materials, equipment and spray method which will be used during production. For prescribed sprayed concrete only test of compressive strength is applicable.

I S BWhen long term experience with similar sprayed concrete equipment and same personnel is available ) preconstruction testing is not necessary. The concrete design and design relationships shall be re-established c ( , when there is a significant change in constituent materials, composition, personal or equipment as indicated below: y p o  changes to higher water/cement ratio C d e  change of aggregate type or supplier l l o r t n  change of max aggregate size o c n  change of admixtures or additives U , 3 0  change of cement supplier 0 2 r e b o t c O 9 0 , h t a B f o y t i s r e v i n U , y r a r b i L h t a B f o y t i s r e v i n U : y p o C d e s n e c i L 18

Licensed Copy: University of Bath Library, University of Bath, 09 October 2003, Uncontrolled Copy, (c) BSI prEN 14487-1:2002 (E)

Table 8 — Preconstruction tests — requirement for the designed sprayed concrete All parameters specified and marked by shadow files in the table, shall be tested Mandatory

Mandatory if specified

Type of work : Inspection Class:

Repair and upgrading 1

2

New structures 3

1

2

Strengthening of ground 3

1

2

3

Property test Test sprayinga Compressive strength Early strength development Frost resistance Water penetration Bond Modulus of Elasticity Additional for fibre reinforced sprayed concrete First peak flexural strength Ultimate flexural strength Residual strengtha Energy absorption capacityb Fibre content a

Amount to be specified to each specific project.

b

Either residual strength or Energy Absorption Capacity can be specified.

19

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7.4

Production control

7.4.1

General

Production control comprises all measures necessary to maintain and regulate the quality of the sprayed concrete in conformity with specified requirements. Production control shall be related to the characteristics of the project including the degree of risk and expected design life. 

Production control consist of following parts



constituent materials control (table 9)

I S  control of basic mix (table 10) B ) c  sprayed concrete properties (table 11) ( , y p NOTE Inspection of execution is covered in EN 14487 Part-2. o C d All relevant data from the process shall be recorded. e l l o r 7.4.2 Constituent materials control t n o c The control of constituent material shall be performed according to table 9. n U , 3 Table 9 — Constituent materials control

prEN 14487-1:2002 (E)

7.4

Production control

7.4.1

General

Production control comprises all measures necessary to maintain and regulate the quality of the sprayed concrete in conformity with specified requirements. Production control shall be related to the characteristics of the project including the degree of risk and expected design life. 

Production control consist of following parts



constituent materials control (table 9)

I S  control of basic mix (table 10) B ) c  sprayed concrete properties (table 11) ( , y p NOTE Inspection of execution is covered in EN 14487 Part-2. o C d All relevant data from the process shall be recorded. e l l o r 7.4.2 Constituent materials control t n o c The control of constituent material shall be performed according to table 9. n U , 3 Table 9 — Constituent materials control 0 0 2 Min sampling frequency r e Material Inspection/test Purpose b Class 1 Class 2 Class 3 o t c O 1 Cements Inspection of delivery To ascertain correct Each delivery 9 ticket type and source 0 , h To ascertain correct Each delivery t 2 Aggregates Inspection of delivery a a type and source ticket B f o 3 Test by sieve analysis To assess compliance first delivery from new y according to prEN 933-1 with standard or other source t i s or aggregate supplier agreed grading r e information v i n Test for impurities or To asses the first delivery from new U 4 , aggregate supplier presence and quantity source y r information of impurities a r b i 5 Additional Test according to To measure the bulk first delivery from new L ISO 6782 density source control for h t light weight a B concrete f o y Relevant materials control must, in case of doubts, be performed independent of inspection class. t i s r 6 Admixtures Inspection of delivery To ascertain if the Each delivery e v ticket and label on consignment is as i n container according to ordered and properly U EN 934-6. marked : y p Inspection of the For comparison with Each delivery o 7 C admixture manufacturer’s stated d value e s n e c i L 20

prEN 14487-1:2002 (E)

Table 9 (continued) Min sampling frequency Material 8

Purpose

Class 1

Class 2

Class 3

Test for density according to ISO 758

For comparison with manufacturer’s stated value

In case of doubt

Inspection of delivery ticket

To ascertain if the consignment is as ordered and from the correct source

Each delivery

10 Additions in Inspection of delivery suspension ticket


Each delivery

11

Test for density according to ISO 758

To ascertain uniformity

Each delivery

12 Water

Test according to prEN 1008:1997-05

To ascertain that the water is free from harmful constituents

If the water is not potable; when new source is used for first time; and in case of doubt

13 Fibres

Inspection of length, diameter and shape


9

Additions bulk powder


Inspection/test

a

Each delivery

According to EN 206-1. (At the delivery at least the origin type and strength class are to be given on t he delivery ticket)

7.4.3

Control of basic mix

The control of the basic mix shall be performed according to table 10. Table 10 — Control of basic mix Min sampling frequency Type of test

Inspection/test

Purpose

Class 1

Class 2

1

Consistence when using wet-mix method

Test according to EN 12350-2 or EN 12350-5

To assess conformity with required class of consistence and to check possible changes of water content

at start of production

2

Admixture content except accelerator

Record of the quantity added

To check the content

Optional

Every batch

3

Additions content

Record of the quantity added

To check the content

Optional

Every batch

4

Fibre content

According to prEN 14488-7

Class 3

Every batch

21

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7.4.4

Control of sprayed concrete properties

If testing is required by the project specification, the sprayed concrete shall be tested according to Table 11. The test frequencies refer to the normal continuous production situation. Four times higher test frequency should be applied in the beginning of a continuous working period or during certain severe parts of a project. However, normally no more than two tests per working day should be necessary. After four following acceptable results, normal frequency shall be applied. The minimum rate of sampling and testing for production control of concrete shall be at the rate, which gives the highest number of samples. The minimum sampling frequencies are valid for production up to the given extension. That is, for minor project, at I least one test sample shall be made where applicable. S B ) c ( , y p o C d e l l o r t n o c n U , 3 0 0 2 r e b o t c O 9 0 , h t a B f o y t i s r e v i n U , y r a r b i L h t a B f o y t i s r e v i n U : y p o C d e s n e c i L 22

prEN 14487-1:2002 (E)

7.5

Conformity criteria

7.5.1 7.5.1.1

General Early strength development

Conformity of sprayed concrete early strength development tested with penetration needle method according to test standard prEN 14488-2 is obtained if the compressive strength f c [MPa] calculated with the mean of at least 10 samples of measured penetration force F [N] within a certain time period of measurement does not exceed the specified field of early strength development (table 12). Table 12 — Conformity criteria for penetration needle method (test standard prEN 14488-2) I Test range up to 1,2 [MPa] S B Maximum grain size 8, 11 [mm] 16 [mm] ) c ( Number of results F [N] Not less than 10 , y p Compressive strength f c [MPa] f c = 0,0015 F + 0,0182 f c = 0,0018 F – 0,0273 o C d e l l Conformity of sprayed concrete early strength development tested with bolt driving method according to test o r t standard prEN 14488-2 is obtained if the compressive strength f c [MPa] calculated with the mean of at least n / L – pull-out force F [MPa] to penetration depth o 10 samples of measured penetration depth L [mm] or the ratio F c n L [mm] – within a certain time period of measurement does not exceed the specified field of early strength Udevelopment (table 13). , 3

prEN 14487-1:2002 (E)

7.5

Conformity criteria

7.5.1 7.5.1.1

General Early strength development

Conformity of sprayed concrete early strength development tested with penetration needle method according to test standard prEN 14488-2 is obtained if the compressive strength f c [MPa] calculated with the mean of at least 10 samples of measured penetration force F [N] within a certain time period of measurement does not exceed the specified field of early strength development (table 12). Table 12 — Conformity criteria for penetration needle method (test standard prEN 14488-2) I Test range up to 1,2 [MPa] S B Maximum grain size 8, 11 [mm] 16 [mm] ) c ( Number of results F [N] Not less than 10 , y p Compressive strength f c [MPa] f c = 0,0015 F + 0,0182 f c = 0,0018 F – 0,0273 o C d e l l Conformity of sprayed concrete early strength development tested with bolt driving method according to test o r t standard prEN 14488-2 is obtained if the compressive strength f c [MPa] calculated with the mean of at least n / L – pull-out force F [MPa] to penetration depth o 10 samples of measured penetration depth L [mm] or the ratio F c [mm] – within a certain time period of measurement does not exceed the specified field of early strength L n Udevelopment (table 13). , 3 0 0 Table 13 — Conformity criteria for bolt driving method (test standard prEN 14488-2) 2 r e Test range 3 to 16 [MPa] b o t c Maximum grain size 8, 11 [mm] O penetration depth L [mm] 9 0 Measured results , pull-out force F [MPa] h t a ratio F / Calculated mean value L [N/mm] B f o Number of results not less than 10 y t i / Compressive strength f c [MPa] f c = 0,13 F L + 0,3511 s r e v i n U Compressive strength , 7.5.1.2 y r a r Conformity of sprayed concrete compressive strength is assessed according to table 14 for: b i L h t  groups of "n" consecutive test results xn (criterion 1); a B f  each individual test result xi (criterion 2). o y t i s r Table 14 — Conformity criteria for compressive strength test results from the structure or from test panels e v i Criterion 1 Criterion 2 n U : Number “ n” of results in the group Mean of “n” results xn in MPa Any individual test results xi in MPa y p o not less than 15 ≥ f ck + 1,48 δ ≥ 0,75 f ck C d 6–14 ≥ f ck + 1,65 δ ≥ 0,75 f ck e s n e c i L 24

prEN 14487-1:2002 (E)

Where: f ck

is the characteristic compressive strength

d

is the standard deviation from, at least 6 samples.

7.5.1.3

Resistance to water penetration

Conformity is obtained if every measured value is lower than the required value. 7.5.1.4 I S B ) c ( , y p o C d e l l o r t n o c n U , 3 0 0 2 r e b o t c O 9 0 , h t a B f o y t i s r e v i n U , y r a r b i L h t a B f o y t i s r e v i n U : y p o C d e s n e c i L

Frost resistance

Conformity is obtained if every measured value is lower than the required value. 7.5.1.5

Bond strength

Conformity of sprayed concrete bond strength is obtained if mean value of a set of samples (normally 3 specimens), is not lower than the required value. 7.5.2 7.5.2.1

Additional for fibre reinforced sprayed concrete: Fibre content

Conformity is obtained if the mean value of measured fibre content from a set of, at least 6 samples, is not lower 3 than V f – 4 kg/m where V f is the target value for the fibre content specified according to preconstruction testing. 7.5.2.2

First peak flexural strength

Conformity of first peak strength is obtained when 

the mean value from test on 3 test samples fulfils the requirement on the first peak strength



no individual test result deviates more than ± 25 % from the calculated mean value.

7.5.2.3

Ultimate flexural strength

Conformity of flexural strength is obtained when 

the mean value from test on 3 test samples fulfils the requirement on the flexural strength



no individual test result deviates more than ± 25 % from the calculated mean value.

7.5.2.4

Residual strength

Conformity of residual strength is obtained when 

At least two of three beams have a residual strength on, or above, the specified residual strength boundary given in Table 2 up to the deflection limit appropriate to the specified deformation level.



The third beam shall for the specified deformation level in no point have a residual stress that is lower than 10 % of the stress corresponding to the boundary of the specified strength class.

25

prEN 14487-1:2002 (E)

AnnexA (informative) Guidelines for Definitions, Specification and Conformity for Sprayed concrete

Foreword This Annex provides guidance and background information on the Normative text. The contents of this Annex are numbered in the same way as the Normative text to facilitate reference, where there is no information a specific I clause, only the title of the clause stated.

S B ) c ( , A.1 Scope y p o The application of sprayed concrete covers the entire field of civil engineering and building construction. It is C d particularly adapted for work under the following special condition: e l l o r  no formwork t n o c  application in thin layers n U ,  early strength 3 0 0 2  special construction methods r e b o t c A.2 Classification O 9 0 A.2.1 Requirements related to exposure classes , h t a The limiting values for composition of concrete related to the exposure classes given in EN 206-1:2000-12 B f clause 5.3, apply for sprayed concrete with the following exceptions: o y t i  Recommendation on minimum cement content does not apply to sprayed concrete s r e v  Recommendation on minimum air content is not applicable. i n U , y r A.2.2 Fibre reinforced sprayed concrete a r b i The different ways of specifying the ductility of fibre reinforced sprayed concrete in terms of residual strength and L energy absorption capacity are not directly comparable. h t a BThe residual strength can be prescribed when the concrete characteristics are used in a structural design model. f o y The energy absorption value measured on a plate can be prescribed when in the case of rock-bolting emphasis is t i s r laid on energy which has to be absorbed during the deformation on the rock. e v i n A.2.2.1 Residual Strength Classes U : y The specification regarding residual strength are related to the deformation conditions of the rock. A higher p o deformation of the rock will demand higher deflection capabilities of the concrete lining. C d e The purpose of the deformation are to give flexibility to the designers in the choice of deformation required of the s n sprayed concrete under service conditions. For the purpose of design, the deflection limit for deformation level can e c i L 26

prEN 14487-1:2002 (E)

be considered in terms of the equivalent angular rotation for bean cracked at midspan (e.g. for a bean of 450 mm × 125 mm × 75 mm test according to prEN 14488-3) Three typical rock deformation ranges have been identified 

D1 corresponding with an angular deformation = l/250







Correspondingly four residual strength levels, S1–S4, are defined which in combination with applicable deformation range, can be specified in terms of residual strength class. I S B ) c ( , y p o C d e l l o r t n o c n U , 3 0 0 2 r e b o t c O 9 0 , h t a B f o y t i s r e v i n U , y r a r b i L h t a B f o y t i s r e v i n U : y p o C d e s n e c i L

An illustrative example is given in figure A.1 for a typical fibre reinforced sprayed concrete bean, this bean fulfils the requirement for residual strength class D1S3 (as well as D2S2 and D2S1).

Figure A.1

A.3 Requirements for Sprayed Concrete A.3.1 Constituent Materials A.3.1.1

Cement

It is of particular importance for sprayed concrete to use cements of consistent properties, especially with respect to its chemical composition, fineness and setting behaviour. If characteristic values as well as requirements to the homogeneity should be defined, the cement supplier and the contractor should agree prior to the start of deliveries.

27

prEN 14487-1:2002 (E)

A.3.2 Requirements for the sprayed concrete composition A.3.2.1

General

Determination of the basic-mix proportions should consider the fact that the quantity of rebound during application will result in a different proportioning of the applied concrete. The composition, especially the content of the cement paste and the water/cement ratio in the basic-mix should, therefore, be so designed that the sprayed concrete on site has the quantity of cement necessary to obtain the required characteristics and strength. An excessive cement content, due to high rebound, can result in excessive shrinkage and a concrete stiffness that will be detrimental to the interaction between old and new parts of the member. A.3.2.2

Use of cement

The cement temperature should not exceed + 80 °C when the cement is delivered from the cement mill and

I + 70 °C when it is filled into the silos of the mixing plant. A higher temperature of the cement delivered from the S Bcement mill is only admissible if precautions to cool the cement before use are taken. ) c ( , A.3.2.3 Use of aggregates y p o CThe use of a properly balanced sieve curve is necessary in order to have enough fine material to assure a good d pumpability of the basic mix (wet process) and a balanced amount of coarse aggregate to achieve the compaction, e l l strength and permeability requirements desired, keeping at a minimum the cement/aggregate ratio (less shrinkage) o r and to help to reduce the rebound rate. t n o c The use of large sized maximum aggregates (especially over 10 mm) may result in a higher rebound. n U , The excess of fines in the mix leads to a higher demand of water. 3 0 0 2 A.3.2.4 Use of admixtures r e b Sprayed Concrete Admixtures o t c OSpecial attention should be given to the adaptation of the cement with regard to the acceleration of setting, early 9 strength and decrease in final strength. Laboratory test methods should be applied for this purpose. 0 , h t With liquid accelerators, special attention should be paid to the storage stability, the working temperature and the a Bcompatibility to water added in accordance to the directions given from the producer. f o y t i A.3.2.5 Use of additions s r e v Use of Fibres i n U , Because of the possible increased proportion of fibres in the rebound, this needs to be taken into account when y r choosing the concrete composition. a r b i It is common practice to use steel fibres up to 30 mm for the dry process and up to 40 mm for the wet process. The L length of the fibres should not exceed 75 % of the internal diameter of the pipes or hoses used unless it has been h t a proven that longer fibres can be used without blockage. If the fibres are added in the form of endless wire directly at Bthe nozzle, even longer fibres may be used. f o y t i The values for a minimum overlap between fibres. s may be estimated as s r e v 2 i π × d f × l f 3 n (A.1) s = U 4 ρ f : y p o where: C d lf length of fibre e s n e d f equivalent diameter of fibre c i L 28

prEN 14487-1:2002 (E)

ρ f

fibre percentage

s

must be lower than 0,45 to ensure a minimum overlap.

Water/cement ratio For dry mix sprayed concrete, the water/cement ratio should be controlled during spraying. In the case of correctly applied sprayed concrete, the water/cement ratio can be expected to be below 0,5. Fines modulus


Due to the spraying process, the control of the water to cement ratio for the dry process is not practical under site conditions for sprayed concrete. To ensure the required resistance against environmental conditions, the content of water and fines ie. fines modulus (cement and aggregates less than 0,25 mm in size) should be controlled at regular intervals during production. The maximum content of water and fines, depending on the exposure classes, should be fixed by the suitability test. This may not apply to accelerated sprayed concrete.

A.3.3 Requirements on hardened sprayed concrete Frost resistance Structures exposed to severe frost action should fulfil the requirements for frost resistant concrete. The type of freeze-thaw test shall be specified in the project specification.

A.4 Specification of sprayed concrete A.4.1 General It is common practice to use the designed mix approach instead of the prescribed mix. A.4.1.1

Basic data

It is difficult to control during application, the water content with the dry process. Usually in situ water/cement ratios are in the range 0,35 to 0,50.

A.5 Assessment of conformity A.5.1 Inspection classification Examples of inspection classes are given in Tables A.1 and A.2.

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Table A.1 — Examples related to strengthening of ground Class

Example of inspection classification

1

Mainly small permanent constructions with minor degree of risk in design and structural instability as well as low durability requirements. Temporary constructions with short design life and low risk of structural instability. EXAMPLE

I S B ) c ( , 2 y p o C d e l l o r t n o c n U , 3 0 0 2 r e b o t c O 9 0 , h t a 3 B f o y t i s r e v i n U , y r a r b i L h t a B f o y t i s r e v i n U : y p o C d e s n e c i L 30



stabilisation’s for small or temporary slopes or building pits



temporary openings or mine openings



pilot tunnels



drifts and headings for large excavations



access tunnels or for temporary use



small storage rooms

Permanent constructions with normal design complexity regarding risk of structural instability or functional safety as well as constructions with moderate durability requirements/design life. Temporary constructions with normal risk in structural instability and normal design life. EXAMPLE 

lining for double-shell constructions



single-shell constructions



storage rooms



low traffic tunnels



public facilities



access tunnels for permanent use



permanent stabilisation’s of slopes and excavation surfaces



exacting mine tunnels



temporary sprayed concrete for tunnels and caverns in poor ground

Permanent constructions with special design complexity regarding risk of structural instability or functional safety as well as constructions with high durability requirements/long design life. Temporary constructions with special risk in structural instability and relatively long design life. EXAMPLE 

caverns in very poor ground



large public facilities



high traffic tunnels



defence shelters

prEN 14487-1:2002 (E)

Table A.2 — Examples related to new structures, repair and upgrading Type of work Kind and use of the structure

New structure

Repair and upgrading

Class

Class

Sprayed concrete categorya Structural Structural


a

non structural

1

Rail or road tunnels with heavy traffic – under sea and river tunnels – sewers in high risk areas – large underground parking – viaducts on major roads – large darns – nuclear power stations – factories classed as high risk – large shopping centres – tower blocks – hospitals – schools – exhibition halls, etc...

3

3

3

2

Rail or road tunnels, bridges, viaducts, etc with medium traffic flow – small shops – apartment blocks – small underground parking – small darns – canals – sewers in medium size urban areas – factories classed as medium risk – power stations – aqueduct for drinking water

3

3

2

3

Tunnels – bridges – viaducts and other structures with light traffic circulation – sewers in small urban zones – small buildings – houses – low risk factories

3

2

1

4

Sewers in un-urbanised zones – aqueducts for industrial water – cable shafts in an environment without risk – no-risk factories

2

2

1

5

Supporting walls in a no-risk zone – open-top aqueduct or canal – surrounding wall

2

2

1

Categories of sprayed concrete

Structural: Sprayed concrete for new structures and for the replacement of deteriorated parts having load-bearing functions. Non structural: Sprayed concrete for the repair of deteriorated parts, having no load-bearing functions, but other functions such as increase of durability or fire protection.

A.5.1.1

Conformity criteria of young sprayed concrete

The very early strength development in between the test range 0,1 to 1,2 [MPa] is measured with the penetration needle method (needle 3 [mm], taper angle 60°). The mean of the values of penetration force F [N] to a depth of 15 mm measured with the penetration needle follow the formula for calculating the early compressive strength f c [MPa] dependent on the specified or chosen maximum grain size: f c 8,11 [MPa] = 0,0015 F + 0,0182

(A.2)

The early strength development in between the test range 1 to 8 [MPa] is measured with the bolt driving method (Hilti DX 450 L, white cartridge). The mean of the values of penetration depth L [mm] determined with the bolt driving method follow the formula for calculating the early compressive strength f c [MPa] dependent on the specified or chosen maximum grain size 8, 11 [mm] in the test range 1-8 [MPa] (figure A 2):

(

)

65,196 −L 0,0598 f c 8,11 [MPa] = e

(A.3)

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prEN 14487-1:2002 (E)

I S Figure A.2 — Calibration curve for bolt driving method (test range 1,0 – 8,0 [MPa]) B ) c ( , The early strength development in between the test range 3 to 16 [MPa] is measured with the bolt driving method y (Hilti DX 450 L, green cartridge). The mean of the calculated values of the ratio F / L [N/mm] (ratio of measured p o penetration force F [MPa] to measured penetration depth L [mm]) determined with the bolt driving method follow Cthe formula for calculating the early compressive strength f [MPa] dependent on the specified or chosen maximum c d grain size 8, 11 [mm] in the test range 3-16 [MPa] (figure A.3): e l l o r t n o c n (A.4) f c 8,11 [MPa ] = 0,13 F / L + 0,3511 U , 3 0 0 2 r e b o t c O 9 0 , h t a B f o y t i s r e v i n U Figure A.3 — Calibration curve for bolt driving method (test range 3,0 – 16,0 [Mpa]) , y r a r b i L The procedure has been calibrated to comm only used sprayed concrete grades. In case of deviations — h t particularly as regards Moh’s hardness or maximum grain size of the aggregates — calibration has to be a Bperformed. f o y t i s r e v i n U : y p o C d e s n e c i L 32

prEN 14487-1:2002 (E)


Figure A.4 — Calibration curve for penetration needle method (maximum grain size 8, 11 [mm]) f c 16 [MPa ] = 0,0018 F − 0,0273 (figure A.4)

(A.5)

Figure A.5 — Calibration curve for penetration needle method (maximum grain size 16 [mm])

33

prEN 14487-1:2002 (E)

AnnexB (informative) General Guidelines for Steel Fibres for Sprayed Concrete

B.1 General This Annex B, gives recommendation for steel fibres used in sprayed concrete. This annex will be superseded when European Standards on Fibre for Concrete are available. I S B ) B.2 Informative References c ( , y EN ISO 9000 Series, Specification for Quality System. p o CprEN 10080-1:1999-10, Steel for the reinforcement of concrete - Weldable reinforcing steel - Part 1: General d requirements e l l o r t n o B.3 Definitions c n U , B.3.1 3 Steel fibres 0 0 Steel fibres are straight or deformed pieces of cold-drawn steel wire, straight or deformed cut sheet fibres, fibres 2 r milled from steel blocks or melt extracted fibres which are suitable to be homogeneously mixed into concrete and e b mortar to be sprayed. o t c B.3.2 O 9 Length 0 The directly measured length is the distance between the outer ends of the steel fibre.The developed length is the , h t distance for deformed steel fibres that are stretched by straightening the steel fibre without deforming the cross a section. B f o B.3.3 y t i Diameter or equivalent diameter s r The diameter of circular steel fibres is determined in accordance with Clause A.6c. The equivalent diameter of non e v circular steel fibres is the diameter of the circle with area equal to the cross-sectional area of the non circular fibre i n and is determined in accordance with Clause A.6c. Later refer to diameter. U , y r B.3.4 a r Aspect ratio b i The ratio of directly measured length to diameter or equivalent diameter of the fibre. L h t a B.3.5 BSteel fibre shape f o The specific outer configuration of the steel fibres, both in the longitudinal direction and in the shape of the cross y t i section and also the possible surface treatments. s r e v i n UB.4 Symbols : y p The symbols listed below are defined as follows: o C 2 d Af is the area of the cross section of the steel fibre, in mm ; e s n d is the diameter or equivalent diameter of the steel fibre, in mm; e f c i L 34

prEN 14487-1:2002 (E)

f f

is the tensile strength of the steel fibre, in MPa;

lf

is the directly measured length of the steel fibre, in mm;

λf

= lf / df is the aspect ratio of the steel fibre.

B.5 Characterisation and product specification The steel fibres shall be characterised as listed below. a) Steel fibres are divided into five general groups and defined in accordance with the basic material used for the production of the fibres. I S B ) c ( , y p o C d e l l o r t n o c n U , 3 0 0 2 r e b o t c O 9 0 , h t a B f o y t i s r e v i n U , y r a r b i L h t a B f o y t i s r e v i n U : y p o C d e s n e c i L



Group I

cold-drawn steel wire



Group II

cut sheet fibres



Group III

milled from steel blocks



Group IV

melt extract



Group V

other steel fibres

b) Steel fibres may be either straight or deformed. In the case of deformed steel fibres, the type of deformation will be declared in the product data sheet. c)

Bundles steel fibres: The type of bundling shall be declared in the product data sheet.

d) The product specifications of steel fibres have to include the following information: 

trade mark and a fibre type designation



length (lf )



diameter (d f )



steel fibre shape



tensile strength



possible additional layer

The characterisation concerns the declared values.

B.6 Determination of characteristic features The following characteristic features have to be determined from 24 steel fibres randomly selected from a shipment or test sample. The characterisation shall be done at least, for each shipment of 20 tons or less, unless the fibres are certified in accordance with ISO 9000 series or a similar system. a)

Trade mark and fibres’ type designation: Use the designation used by the manufacturer or supplier

b)

Length:

35

prEN 14487-1:2002 (E)

The average length of the 24 steel fibres and the standard deviation are determined. In the determination of the length of a steel fibre, a distinction can be made between the directly measured length and the developed length. The directly measured length is the distance between both ends measured with a calliper square. The average of all the measured values is determined. To determine the average developed length the total length of the 24 straightened steel fibres, joined together in one row, is measured and subsequently divided by the total number of 24 steel fibres. c)

Diameter: In the case of circular steel fibres, the diameters of the 24 steel fibres are measured with a micrometer calliper and subsequently the average of the measured values is determined.

I S In case of non-circular cross-section, the average equivalent diameter is determined by first establishing the B total weight of the 24 steel fibres. Subsequently, the volume of the steel fibres is determined on the basis of an ) 3 c assumed density of 7 850 kg/m . Division of the volume by the overall developed length of the 24 steel fibres ( , results in the equivalent area of the cross-section, from which the equivalent diameter can be derived. y p o Cd) Aspect ratio of the steel fibre: d e l l Subsequent to the determination of the average directly measured length and the equivalent diameter from the o r 24 steel fibres, the aspect ratio can be established. t n o c e) Steel fibre shape: n U , The shape of the steel fibre is checked on the basis of the descriptions and/or drawings provided by the 3 0 manufacturer or the supplier. 0 2 r f) Tensile strength: e b o t The tensile strength of the 24 steel fibres is determined in conformity with the methodology described in c O prEN 10080-1:1999-10. 9 0 , g) Additional coating: h t a If the steel fibres have been supplied with any coating (e.g. zinc coating), the characteristics of the coating B f shall be given in the product data sheet. o y t i s r e B.7 Tolerances v i n UThe tolerances for the determination of the characteristics described in A.6 are given in Table B.1. , y r a r Table B.1 — Tolerances b i L h Property Deviation of the individual value Deviation of the average value t a relative to the declared value relative to the declared value B f o Length l f ± 10 % ±3% y t i (equivalent) diameter d f ± 10 % ± 0,03 % s r e v Tensile strength f f N/mm2 ± 15 % ± 7,5 % i n U Length/diameter ratio ± 15 % ± 7.5 % : y p o C d e s n e c i L 36

prEN 14487-1:2002 (E)

B.8 Packaging The steel fibres have to be packed in such a way that they are sufficiently protected against detrimental effect during transport and storage. Every delivery shall contain only one type of material and one single size, unless otherwise agreed upon. Every container has to be marked with the type of fibre, the net weight and the name or trade mark of the manufacturer.


37

Sprayed Concrete

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