KKKH4254 PROJEK REKABENTUK II
____________________________________________________ ________________________ ____________________________________________________ ________________________ TAJUK PROJEK:
COURSE OUTCOME & PROGRAMME OUTCOME ―PROJEK CAPSTONE BAGI CADANGAN PEMBINAAN PROJEK PEMBINAAN SEKOLAH MENENGAH KEBANGSAAN PUNCAK JALIL‖
NAMA: MOHD GAZALI BIN ALIMUDDIN NO MATRIK : A128044 JABATAN: JABATAN KEJURUTERAAN AWAM DAN STRUKTUR TAHUN: 4 NAMA PENSYARAH:
PROF.IR.DR.WAN HAMIDON BIN WAN BADARUZZAMAN PROF.IR.DR.RIZA ATIQ ABDULLAH BIN O.K.RAHMAT PROF.MADYA.IR.DR.OTHMAN BIN JAAFAR
COURSE OUTCOME 1 “Able to identify and describe project site and constraints including existing topography and terrain, sub-soil conditions, conditions, Civil Civil Engineering Engineering accessibility, drainage, water supply, important to sustainability development.”
infrastructure facilities facilities (road (road and
and sewerage systems (if any), and elements elements
PROJECT BACKGROUND
The construction project of Puncak Jalil secondary school was estimated to accommodate about 500 students at any one time per session. The location is close to the main campus of the National University of Malaysia Bangi branch, Teras Jernang Village and Taman Desa Sentosa. The contract was estimated to be valued at RM 11,470,000.00 and is expected to be completed within 24 months (2 years) from the date of its construction on May 25, 2013. The estimated construction area spans was approximately 9,360,000 m2 which is equivalent to 936 hectares and is certainly extensive use of land space. If viewed from the background of the project area, this area was a virgin forest which the oil palm and forest shrub that has long been neglected were vegetated. In terms of the appearance of the ground is moderately high hills, where the highest peak on contour record at 42.68 meters above sea level and the lowest contour level was recorded at 19.81 meters above sea level. This project area is located near the Langat river and the nearest residential area are Teras Jernang Village (1.3 km) and Taman Desa Sentosa (2.2 km). Figure 1: Topographic maps of the project site area
Figure 2: Polygon map of the project site area a rea
ACCESSIBILITY
Construction of the proposed project area is adjacent to the road Bangi. This road link between Jalan Reko and Jalan Kajang-Dengkil. Data on traffic flow in this area is not available because it would require a long process to get it from the traffic police, road transport department and public works department. Researchers simply made a statement through observation. Through the observation, traffic conditions on the road will be crowded during peak hours, from 6 am to 9 am and 5 pm to 7 pm. Traffic flow will be high in some areas such as the three junction in Figure 3 below. This is because it connects traffic moves from Kajang or from Bandar Baru Bangi to the Teras Jernang village and from Dengkil or from teras jernang village to kajang or to Bandar Barru Bang.. This observation was usually done at random and through researcher experience. Among the factors that enable high congestion in the area is due to the public facilities available in the Village Core Jernang. Public facilities available in this area rather draw attention to the surrounding area. Furthermore, Teras Jernang Village is also close to the area of higher
education institutions such as the National University of Malaysia Bangi branch and Mara Polytechnic College. This boost traffic flow at peak times. Among the public facilities that are available in this area such as food outlets facilities, photostat centers, workshops, cars and motorcycles, retail shops, mosques, and dormitories to be occupied by undergraduates and students who live outside of their campus area. Among other factors which may invite to the increase in traffic flow is caused by factors existing roads can not cope with the flow of vehicles in and out of traffic at a time, especially during peak hours. This study suggests that road widening is done. This not only cause problems to the traffic flow in road but also the safety of the user of the road was a concern. If
the
construction project commenced, it is feared the traffic flow rate will also increase due to the presence of the trucks and construction machines will be in and out through the road. So in this report, the researcher will be more emphasis on road construction backup to Puncak Jalil Secondary School Project in terms of the proposed site, construction methods, construction impact, and sustainability can be proclaimed in this project.
Figure 3: The three junction of Jalan Bangi
Figure 4: The path to the project site area
STREAM AND WATER BODIES
The nearest stream and water bodies that can be detected from the site project is Langat river. This river were flowing from Nuang mountain in the state of Hulu Langat and flowing to the Straits of Malacca in Kuala Langat. The length of this river is 149.3 km upstream to the mouth of the river. There are some towns and villages were built on the banks of the Langat River. Among them are Dusun Tua, Ulu Langat, Cheras, Kajang, Sungai Chua, Jenderam, Dengkil, Manggis River, Olak Lempit, Banting, Jenjarom, Teluk Dato, Teluk Panglima Garang and Bandar Baru Bangi. Langat River is very important when tin ore became the main industry in the state. Among the important tin ore area is Sungai Besi, Balakong, Kajang, Sungai Chua, Cheras, Serdang and Semenyih. A dam for drinking water have been built at the upstream of Sungai Langat called Sungai Langat dam or Pongsun dam. Semenyih river is the branch of the Langat River. Both rivers are heavily polluted at some time ago, especially by sawmill in Cheras and pig feces in Semenyih. This river was also the main source of raw water to seven water treatment plants in Selangor that are Sungai Langat Water Treatment Plant, Bukit Tampoi Water Treatment Plant, Cheras Batu 11 Water Treatment Plant, Salak Tinggi Water Treatment Plant, Sungai Pangsoon Water Treatment Plant, Sg Serai Water Treatment Plant and Sg LoloWater Treatment Plant. The process of rapid modernization and development, especially in Selangor, Sungai Langat water contamination threat is so severe that contribute to the water crisis. According to reports Malaysia Environmental Quality Report 2006, published by the Department of Environment, some rivers that flow from the Langat River was contaminated with the Water Quality Index of rivers is at level III. These rivers are Sungai Balak, Batang Benar, Batang Nilai, Sungai Lui and Sungai Pajam. On October 11, 2012, Chief Environmental Modelling Unit, Centre for Environment Forensic Research (ENFORCE) Universiti Putra Malaysia, Dr Hafizan Juahir states that only
49.3km from 149.3 km Sungai Langat is still clean. 100 miles further is contaminated and unfit for drinking water. 100km Langat River is already in grade 3, 4. If the water quality is worse than this, it is considered as dead river. The main factor pollute this stream is the dry water, domestic waste and garbage in the river.
Figure 1: Langat River taken from Kajang
Figure 2: Langat River from GIS
Figure 3: Langat Basin
Figure 4: Sungai Langat branch
DRAINAGE SYSTEM
Drainage system was designed and built with the intention of discharge water to the lowest catchment area. Good drainage and efficient to be highly beneficial especially to the process to control and prevent flooding. The good and efficient drainage will facilitate the flow of water and reduce the impact of pollution on water quality. It also will prevent natural disasters such as floods. The advantages of drainage in road construction, it can reduce the occurrence of water ponding problems on the road surface. This problem can cause damage to the surface of the road. This can have a direct effect on the safety of road users and also increase the cost of maintenance of the roads. In general, drainage system serves to drain the surface runoff from the buildings, paved areas, the roads and other impervious area to a safe area such as a river, lake or sea. Good drainage is essential to protect the interests of economy, social security and certain areas. A good drainage system must be able to accommodate the amount of runoff received.
Types of Drainage System
There are different types of drainage systems in various forms, but the type of drainage system is divided into two basic systems that was initiation drainage system and m ain drainage system
Initiation Drainage System
The initiation drainage system is a system that carries runoff from its specific area. For example, from housing or industry runoff is brought to the main drain and the main drainage of runoff draining into the catchment area such as rivers, lakes and seas. Initiation drainage systems are usually designed for repeated periods of 2 or 5 years depending on land use planning. The beginning of the drainage system usually includes:
o
Drain or roadside ditch
o
Street gutter
o
Sewerage
o
Water run-off pipe
o
Other structures designed to carry runoff
Main Drainage System
The most important municipal drainage system is the main drainage system in which the effectiveness of a network of a main drainage system is dependent on the planning and design of main drainage. The main purpose of the main drainage system is the amount of runoff collector system from the beginning of the drainage system to the river, lake or sea. The main drainage system designed for repeated periods of 100 years to reduce damage to life and property due to flooding. The system consists of:
o
Natural and man-made drainage
o
Underground Drainage
o
Drainage on the road
o
Other drainage structures
Through observations on the types of drainage in the project area, the type of drainage there are more to the initiation drainage system type. This type of drainage can be seen at the roadside of Bangi road. Surface water runoff from the road surface will be routed to the roadside ditches and it will be drained into the Langat river.
Figure 6: Example of Drainage implemented in Jalan Bangi
Through observation on the roadside ditch in Jalan Bangi, the drainage was getting shallow. It might be caused by the soil erosion that occurs at the edge near the side of the road when heavy rain happened. The water runoff that came from the forest near Jalan Bangi was bringing the water and also the sediment which lead to this problem.
WATER RESOURCES
Available water resources in the project area is under the purview of the Selangor Water Supply Company (SYABAS). SYABAS is a state government-linked company in charge of water supply service in Selangor and the Federal Territory of Kuala Lumpur and Putrajaya. SYABAS was established on July 8, 1996 under the Malaysian Companies Act 1965. Selangor Water Management Corporation Berhad (PUAS) are subsidiaries of the company SYABAS. The executive chairman of SYABAS is Tan Sri Rozali Ismail. As we know, the distribution water resources can be categorized into three types, namely a gravity system, pumping system and a combination of gravity and pumping system. SYABAS
distributed water to each area using the pump system. Water was pump to the consumers from the Langat River water treatment plant.
Sungai Langat Water Treatment Plant
IMPORTANT ELEMENTS TO SUSTAINABLE DEVELOPMENT WE MEAN BY
―SUSTAINABILITY‖ While many of the definitions offered by other authors or political groups address the three central and well recognized themes of sustainability (ecology, economy and equity, a.k.a. the ―triple bottom line‖), none of these definitions are directly actionable at a project level and are of little utility when considering sustainability from the perspective of a transportation designer or contractor. This is for two particular reasons:
1. Lack of project‐level context and specific tangible constraints, and 2. Lack of incentive or drivers to progress sustainability in a meanin gful way.
However, three key broader ideas are consistent in most of the definitions: physical constraints or laws of Nature ( natural laws), satisfaction of basic human needs and desires (human values), and the idea that roadway projects are best perceived as systems of varying degrees of complexity, interdependence, scale and context. These three terms are clarified in detail below.
A useful, implementable definition of sustainability for roadway projects must feature these three terms because these ideas are simple to understand and explain to project stakeholders. Importantly, how well a particular project fits these project‐specific natural law and human value constraints is a characteristic or trait of that system that is measurable (in terms of quantity and/or quality). This means sustainability on one roadway project can be compared to other roadway projects, and ultimately, sustainability becomes manageable on both short‐ and long‐term time scales. Therefore, sustainability is a system characteristic that reflects its capacity to support natural laws and human values.
NATURAL LAWS
―Natural laws‖ encompass the essential idea of Ecology, which is the study of ecosystems. These concepts are illustrated by the simple, but oxymoronic idea that ecosystems are too complex to be fully controlled or understood by humans, and that our best control and understanding comes from basic sciences like physics, chemistry and biology. Effectively, mathematics and sciences are the tools by which we measure the limits and current status of our environment. These natural laws form the physical constraints within which all projects must fit, regardless of how much control we think we may have over our own environment as humans or how complete or certain the science is perceived to be.
We must understand that our conventional understanding of natural laws is at best incomplete and at worst could be totally wrong. Humans live and operate within the context of ecosystems, not vice versa (as indicated by current trends in civil development). The paradigm in which we live, operate and behave must therefore shift to a more sustainable one under our best possible and most current understanding of ecology, such as that proposed by The Natural Step framework, which offers a system‐ based approach to sustainability guided by three basic principles as follows:
Substances should not be extracted from the Earth at a rate faster than they can be regenerated by natural processes.
Substances (waste) should not be produced at rate faster than they can be decomposed and reintegrated into an ecosystem.
Ecosystems should not be systematically degraded or otherwise disrupted from equilibrium by human activities.
Conventional roadway design and construction practices and systems do not support these three above principles consistently; however, a significant amount of academic and industry research in a variety of fields indicates that the y can.
HUMAN VALUES
Similarly, ―human values‖ (basically Robèrt‘s fourth principle) include both equity and economy. Equity can be broadly understood as seeking quality of life for all: ultimately this
means satisfaction of basic human needs within a specific cultural context. Human needs have been well studied in psychology and social sciences. The most prevalent ideas regarding human needs can be defined by either a hierarchical model, such as that proposed by Maslow or a taxonomic model. Maslow identified physiological needs, safety, belonging, esteem and selfactualization as tiers of needs. Max‐ Neef et al. identified nine unique needs that vary according to the process by which they are satisfied (being, having, doing, and interacting): subsistence, protection, affection understanding, participation, leisure, creation, identity, and
freedom. For the sustainability purposes, either psychological model is fitting to best illustrate the idea of human values. The basic idea is that all humans have the same needs, the value of these needs can change with time, and there is a wide variety and varying degree to which needs are satisfied and managed in different communities and cultures.
There are a number of tradeoffs that occur when meeting more than one need simultaneously. These societal constraints, including regulations and policy, govern the idea of Economy, which means, simply, management of financial, natural, manufactured, and human
capital resources. The concept of economy can be scaled down to apply to project‐level financial choices or scaled up to more broad practices of resource management such as sustainable forestry, waste management or carbon cap‐and‐trade arrangements. Again, however, conventional roadway design and construction practice does not support these needs, or address their dynamics and management, consistently on all projects.
SYSTEMS AND SUSTAINABILITY
Clearly, a systems‐ based approach to sustainability renders a definition that includes only Ecology, Equity, and Economy incomplete. In addition to these components, sustainability is context‐sensitive. Specifically, a roadway project system‘s context is sensitive to whatever human needs and values are defined by the management team and stakeholders and its environmental setting. These are the constraints, or boundaries, within which project decisions must be made. Therefore, two more critical sustainability components, extent and expectations, are identified. These two components act as the system boundaries, providing scope and context to sustainability. Extent represents the idea that a project system has well‐defined constraints and limits
within which sustainability can be measured. Extent refers to spatial and temporal constraints of civil projects (such as centerline length, right of way dimensions, footprint, and service life, respectively) often explicitly defined by natural laws (such as how gravity ultimately defines load limits). Some other practical examples of extent are height restrictions and construction working hours.
Performance criteria, or Expectations, are the key human value constraints identified for the project. Expectations provide the equity and economic context within which the overall performance of the system is most effectively judged. Expectations vary by project and may include practical performance of the individual design elements, overall quality of the construction processes of a project, or system‐wide outcomes like reduced accidents or improved worker productivity. While the ideas of Extent and Expectations may be implicit (or presumed to be understood) in the preceding descriptions of natural laws and human values, there is no reason for them not to be explicitly stated in working definition of sustainability. In fact, without explicitly stating these components, it is more likely that misunderstandings of these critical limits, boundaries, and constraints would occur, or that their impacts and importance would be ignored or downplayed. Furthermore, it is not enough to believe that the idea of sustainability will self ‐ propagate and implement its own paradigm shift toward more sustainable systems and practices. Thus, the final two important components of sustainability, Experience and Exposure, translate the philosophical concept of sustainability into implementable practices. Experience represents both what has been learned and the learning process itself, which is ongoing. So, experience includes technical expertise, innovation, and knowledge of applicable historical information, which is critical in decision‐making processes. For example, most successful project teams are comprised of interdisciplinary experts that can bring specialized experience to design or construction. Finally, if the concept of sustainability is to cause a paradigm shift in individual, community and societal behaviour then it must include an active educational component; or more specifically, a teaching or outreach component. Exposure represents the idea that implementing sustainability in practice requires ongoing educational and awareness programs for the general public, professionals, agencies, and stakeholders. Therefore, experience and exposure drive the progress and implementation of sustainability within a project system. Without these two driving components, civil engineering systems would remain static, and sustainability would be absent, unmanageable or simply unrecognized.
COURSE OUTCOME 2 “Able to critically assess and evaluate the project site before coming up with design concepts and solutions. To include any sign of distress such as erosion, soil condition, distance to the nearest existing facilities, accessibility, anticipated difficulties, etc.”
SITE SELECTION
Generally the selection of a site for a project to be carried out, the parties of builder responsible should do the necessary procedures to ensure the project site in accordance with the requirements of the construction project to be carried out. One of the procedures or methods to ensure execution of the project requirements is to perform the site investigation.
SITE INVESTIGATION
A detailed site investigation and comprehensive is necessary at an early stage in the design and construction of civil engineering works. Site investigation usually depends on the size and type of projects or work. In fact in certain circumstances (small works) also require site investigation. Adequate site investigation should be done before a civil engineering work is done. Sufficient information must be obtained to achieve a safe and economic design, as well as to avoid any inconvenience during construction. The main purpose of the investigation is; 1. To determine the order of the thickness and area of the side of a layer of soil and bedrock level, if necessary. 2. To obtain a representative sample of soil (and rocks) for the purpose of identification and classification, and, if necessary, be used in laboratory tests to determine the appropriate soil parameters. 3. To identify groundwater conditions. Investigation also included achievement tests in situ to assess the characteristics of suitable land. Results of an investigation should provide complete information, for example to determine the selection of the most appropriate basis for a proposed structure and to indicate if there would be problems during dredging. BS5930: 1981 "Code of Practice for Site Investigation"; listed the objectives of the site investigation such as below: i.
Assess the suitability of the site and surroundings of the proposed work as a whole.
ii.
Help to provide a complete work or design, economical and safe. This includes temporary works.
iii.
To plan the best construction methods, making various surveys of potential problems or difficulties in construction and thus can provide a solution to the problems that arise.
iv.
To obtain information about possible changes in the site and surrounding area either natural or occur as a result of work done. Also information on the impacts of these changes on the work of the ongoing construction site area.
v.
To obtain a more suitable area where there is construction site area (if there are 2 options or more). No matter whether in the area of the construction site or at different construction sites. In general, site investigation should be completed before the design stage of a project.
However, there are also 'overlapping', especially in massive civil engineering works and usually involve specific tests that cannot be avoided.
The selected site construction was as figure above. We are choose this area because it is easy to access which can lowering the cost of transportation of the machineries and lorries. We also look and investigate at the condition of the land in the project area. We believed that the area we choose were less sloping if compared to the other area which is more sloping. We also choose this area because it is near to jalan Bangi, and we do not want to reclaim too much to the forest while doing the site clearing process.
SOIL CLASSIFICATION
Soil classification is usually based on profile attributes, with the land was formed under the same conditions and have features that are placed in regular classes. Classification and taxonomy now is important in many disciplines including civil engineering. There are many methods and study to identification and classification of land was used and done. For particle size analysis, hydrometer method was used to obtain the content of sand, silt and clay without separating the land. In addition, to estimate and to get the texture of soil was usually done during the check soil in the field. Scientists use field methods to obtain multi-layer on the soil texture and differentiate
between different soil on the landscape. Taken and moistened soil to form a ribbon and the ribbon shape determined from the nature of the soil texture. In this project, we will studies the soil classification and analyzing it through the geological map just like in Figure 7. From the map below we can concluded that the classification soil in the site project were categorized as a soil that going through the Devonian event, which is rich in clay subsoil.
Figure 7: Geologic map
Roadwork in clay surface was a big task and responsibilities to be done. This is because the clay soils contained water and the water was a big enemy to the road. If the engineer just built the road on the surface like this, it can cause corrugated (excessive settlement) when the rain came and maybe the subbase also might be swallowed downward. The solution that could adapt this problem is build some drainage and also see the material used to contruct the road. The engineer can first dig up the road and replace the sub
surface of sand and clay with crushed gravel that would not become compacted. The next was to construct drainage ditches on either side of the road with culverts under the road that would allow free drainage of the ground water. The drainage is everything here. It is the subsurface flow of ground water that causes the major damage to a road, paved or gravel. Water has to flow freely. When the road becomes a dam, the water is forced to the surface where it creates the washouts, pot holes and quicksand. Other solution that can be made is by installing a Geogrid such as a copolymer plastic grid made by Tensar Figure 8, or an equivalent product, first laid down on the prepared clay soil subgrade, than followed with a fairly thick compacted subbase course of well-graded and drained gravel. Don't just install a geofabric over the clay because it will deflect and possibly tear. Eventually it will have severe rutting that mirror images the displacement of the clay subgrade below. Using the Tensar Geogrid acts like a snowshoe helping to disperse (spread out) vehicle wheel loads plus it keeps the subbase materials from migrating into the clay subgrade. To determine the proper geogrid material as well as the subbase gravel material and thickness is going to take the expertise of a qualified Geotechnical Engineer, who may have to perform field and laboratory soil testing.
Figure 8: Implementation of Geogrid made by Tensar
NEAREST EXISTING FACILITIES
The nearest facilities that can be seen near the site construction project was food outlets facilities, food stalls, photostat centers, cars and motorcycles workshop, retail shops, mosque, dormitories, and higher learning education centre. Figure 8: Retail shops
Figure 9: As-Solihin Mosque
Figure 10: Dormitories
Figure 11: National University of Malaysia
Figure 12: Poly-Tech Mara College
COURSE OUTCOME 3 Able to develop and propose design concepts and solutions for infrastructure elements design that incorporate sustainable development criteria (choice of site, construction techniques and materials such as the use of Industrialised Building System (IBS) etc.), economics, health and safety, ethics, etc.
ROAD CONSTRUCTION
INTRODUCTION
Road construction requires the creation of a continuous right-of-way, overcoming geographic obstacles and having grades low enough to permit vehicle or foot travel and may be required to meet standards set by law or official guidelines. The process is often begun with the removal of earth and rock by digging or blasting, construction of embankments, bridges and tunnels, and removal of vegetation (this may involve deforestation) and followed by the laying of pavement material. A variety of road building equipment is employed in road building. After design, approval, planning, legal and environmental considerations
have
been
addressed alignment of the road is set out by a surveyor. The radii and gradient are designed and staked out to best suit the natural ground levels and minimize the amount of cut and fill. Great care is taken to preserve reference Benchmarks. Roads are designed and built for primary use by vehicular and pedestrian traffic. Storm drainage and environmental considerations are a major concern. Erosion and sediment controls are constructed to prevent detrimental effects. Drainage lines are laid with sealed joints in the road easement with runoff coefficients and characteristics adequate for the land zoning and storm water system. Drainage systems must be capable of carrying the ultimate design flow from the upstream catchment with approval for the outfall from the appropriate authority to a watercourse, creek, river or the sea for drainage discharge. A borrow pit (source for obtaining fill, gravel, and rock) and a water source should be located near or in reasonable distance to the road construction site. Approval from local authorities may be required to draw water or for working (crushing and screening) of materials for construction needs. The top soil and vegetation is removed from the borrow pit and stockpiled for subsequent rehabilitation of the extraction area. Side slopes in the excavation area not steeper than one vertical to two horizontal for safety reasons.
Old road surfaces, fences, and buildings may need to be removed before construction can begin. Trees in the road construction area may be marked for retention. These protected trees should not have the topsoil within the area of the tree's drip line removed and the area should be kept clear of construction material and equipment. Compensation or replacement may be required if a protected tree is damaged. Much of the vegetation may be mulched and put aside for use during reinstatement. The topsoil is usually stripped and stockpiled nearby for rehabilitation of newly constructed embankments along the road. Stumps and roots are removed and holes filled as required before the earthwork begins. Final rehabilitation after road construction is completed will include seeding, planting, watering and other activities to reinstate the area to be consistent with the untouched surrounding areas. Processes during earthwork include excavation, removal of material to spoil, filling, compacting, construction and trimming. If rock or other unsuitable material is discovered it is removed, moisture content is managed and replaced with standard fill compacted to meet the design requirements (generally 90-95% relative compaction). blasting is not frequently used to excavate the road bed as the intact rock structure forms an ideal road base. When a depression must be filled to come up to the road grade the native bed is compacted after the topsoil has been removed. The fill is made by the "compacted layer method" where a layer of fill is spread then compacted to specifications, the process is repeated until the desired grade is reached. General fill material should be free of organics, meet minimum California bearing ratio (CBR) results and have a low plasticity index. The lower fill generally comprises sand or a sand-rich mixture with fine gravel, which acts as an inhibitor to the growth of plants or other vegetable matter. The compacted fill also serves as lower-stratum drainage. Select second fill (sieved) should be composed of gravel, decomposed rock or broken rock below a specified Particle size and be free of large lumps of clay. Sand clay fill may also be used. The road bed must be "proof rolled" after each layer of fill is compact ed. If a roller passes over an area without creating visible deformation or spring the section is deemed to comply. Geosynthetics such as geotextiles, geogrids and geocells are frequently used in the various pavement layers to improve road quality. Geosynthetics perform four main functions in roads: separation, reinforcement, filtration and drainage; which increase the pavement performance, reduce construction costs and decrease maintenance.
The completed road way is finished by paving or left with a gravel or other natural surface. The type of road surface is dependent on economic factors and expected usage. Safety improvements like Traffic signs, Crash barriers, Raised pavement markers, and other forms of Road surface marking are installed. SCOPE OF ROADWORK
The main scope of road construction works are:
Cleaning of site
Work surveying / setting out
Work clay excavation, cut, reclaimed
Treatment of soil
Construction of road structure
Build a bridge
Building drainage system
Build a retaining wall
Construction of slope protection
Install / hold street furniture
Install street lighting / traffic lights
Environmental management
Traffic Management
ROUTE LOCATION
For the project which is totally new road, a study shall be made on the various alternative alignments to determine the most feasible one. The route can be determined with the assistance of one or more of the following: I.
Topographic sheet.
II.
Aerial photographs.
III.
Existing and future development plans from the Town Planning Department.
IV.
Revenue sheet.
V.
Design and /or as-built plans of the existing road i n the case of road improvement.
In determining the route the engineer shall take into consideration factors such as the ground terrain, waterways, existing properties and subsoil conditions. An estimate of the length of the road in kilometer shall also be made. Where the final alignment of the proposed road or improvement is not yet determined, the Consulting Engineer shall undertake field reconnaissance and preliminary surveys, etc. to determine the best corridor for an alignment and shall proposed several alternative routes for selection. The routes shall be selected according to topographic, geologic, economic and social political factors. Besides, when there is no feasibility study carried out for the project, the engineer shall determine the most suitable alignment. Preliminary ground survey need not be carried out if as built-up plans available. If such plans are available, the engineer can proceed on to the design of the final horizontal alignment.
SELECTION OF FINAL ALIGNMENT CONTROL
The chosen alignment shall follow closely where practicable, the alignment of the existing road so as to keep the cost to the minimum and also for the various following reasons: I. II.
Avoid additional land acquisition. Keep to a minimum any adverse impact on social, environmental aspects. Reutilized existing bridges, culverts, drain structures and even pavement whereve r possible.
III.
Minimize relocation of public utilizes and in particular the high tension transmission towers, which may not be relocatable in many cases.
The Engineer shall check and ensure that his design satisfy the minimum requirement of the following geometric element: I. II.
Stopping sight distance. Passing sight distance.
III.
Transition length.
IV.
Minimum radius.
LAND ACQUISITION PLAN
The consulting Engineer is responsible for preparing land acquisition plans to enable the client to acquire the necessary right-of-way. The plans shall be of a scale accepted by the Land Office and must define clearly the limits of the right-of-way required by the project. The land acquisition plan shall include details of Lot Numbers and areas of each individual lot that has to be acquired and coloured appropriately in accordance with the requirement of the Land Office. The surveyor shall compile and prepare base plans for property and land acquisition proposes from the Survey Department cadastral sheet and latest revenue sheets from the Land Office and other Government land scheme agencies where relevant to the same scale.
ROAD CLASSIFICATION / HIERARCHY
The Importance of Road Classification
The importance of defining a hierarchy of roads is that it can help clarify policies concerning the highway aspects of individual planning decisions on properties served by the road concerned. Furthermore specific planning criteria could be developed and applied according to a road‘s designation in the hierarch: for example design speed, width of carriageway, control over pedestrian, intersections, frontage access etc. In this way the planning objectives would be cle ar for each level of road in the hierarchy and policies on development control and traffic management would reinforced one another.
Functions of Road
Each road has its function according to its role either in the National Network, /regional Network, State Network or City/Town Network. The most basic function of a road is transportation. This can be further divided into sub-functions; namely mobility and accessibility.
However, these two sub-functions are in trade off. To enhance one, the other must be limited. In rural areas, roads are divided into five categories, n amely:
Expressway.
Highway.
Primary Road.
Secondary Road.
Minor Road.
While in the urban areas, roads are divided into four categories, namely:
Expressway.
Arterial.
Collector.
Local street.
Road Category and Their Application
Categories of roads in Malaysia are defined by b y their general functions as follows: a) Expressway An Expressway is a divided highway for through traffic with full control of access and always with grade separations at all intersections. In rural areas, they apply to the interstate highways for through traffic and form the basic framework of National road transportation for fast travelling. They serve long trips and provide higher speed of travelling and comfort. To maintain this, they are fully access controlled and are designed to the highest standards. In urban areas, they form the basis framework of road transportation system in urbanized area for through traffic. They also serve relatively long trips and smooth flow and with full access control and complements the Rural Expressway.
b) Highway They constitute the interstate national network for intermediate traffic volumes and complements the expressway network. They usually link up directly or indirectly the Federal Capital, State Capitals, large urban centres and points of entry/exit to the country. They serve long to intermediate trip lengths. Speed of travel is not as important as in an Expressway but relatively high to medium speed is necessary. Smooth traffic is provided with partial access control.
c) Primary Roads They constitute the major roads forming the basic network of the road transportation system within a state. They serve intermediate trip length and medium travelling speeds. Smooth traffic is provided with partial access control. The y usually link the State Capitals and district Capitals or other Major Towns.
d) Secondary Roads They constitute the major roads forming the basic network of the road transportation system within a District or Regional Development Areas. They serve intermediate trip lengths with partial access control. They usually link up the major towns within the District or Regional Development Area.
e) Minor Roads They apply to all roads other than those described above in the rural areas. They form the basic road network within a Land Scheme or other sparsely populated rural area. They also include roads with special functions such as holiday resort roads, security roads or access roads to microwave stations. The serve mainly local traffic with short trip lengths with no access control.
f) Arterials An arterial is a continuous road within partial access control for through traffic within urban areas. Basically it conveys traffic from residential areas to the vicinity of the central business district or from one part of a city to another which does not intend to
penetrate the city centre. Arterials do not penetrate p enetrate identifiable neighbourhoods. Smooth traffic flow is essential since it carries large traffic volumes.
g) Collector A collector road is a road with partial access control designed to serve as a collector or distributor of traffic between the arterial and the local road systems. Collector are the major roads which penetrate and serve identifiable neighbourhoods, commercial areas and industrial areas.
h) Local Streets The local street system is the basic road network within neighbourhood and serves primarily to offer direct access to abutting land. lan d. They are links to the collector road and thus serve short trip lengths. Through traffic should be discouraged.
Area
Road Categories
Rural
Trip Length
Long
Med
Short
Design Volume
High
Med
Low
Speed
High
Med
Network
Low National
Expressway
Network National
Highway
Network
Primary
State
Road
Network
Secondary
District
Road
Network
Minor Road
Supporting Network
Urban
National
Expressway
Network Major
Arterial
Links to Urban Centres Major
Collector
Streets to Urban Centres Minor
Local Street
Streets/ Town Network
Table 1: Characteristic of Road Categories
Application of Design Standards for Roads
The design standard is classified into six groups (R6, R5, R4, R3, R2, R1) for rural areas and into six groups (U6, U5, U4, U3, U2, U1) for urban areas. Each of these standards are listed below with descending order of hierarchy. a) Standard R6/U6: Provides the highest geometric design standards for rural or urban areas. They usually serve long trips with high travelling speed of travelling, comfort and safety. It is always designed with divided carriageways and with full access control. The Rural and Urban Expressway falls under this standard.
b) Standard R5/U5: Provides high geometric standards and serve intermediate trip lengths with medium travelling speeds. It is usually with partial access control. The Highway, Primary Road and Arterial fall under this standard. It is sometimes designed as divided carriageways with partial access control.
c) Standard R4/U4: Provides medium geometric standards and serve intermediate trip lengths with medium travelling speeds. It is also usually with partial access control. The Primary Road, Secondary Road, Minor Arterial and Major Collector fall under this standard.
d) Standard R3/U3: Provides low geometric standard and serves mainly local traffic. There is partial or no access control. The Secondary Road, Collector or Major Local Streets are within this standard.
e) Standard R2/U2: Provides low geometric standards for two way flow. It is applied only to local traffic with low volumes of commercial traffic. The Minor Road and Local Streets fall under this standard.
f) Standard R1/U1: Provides the lowest geometric standards and is applied to road where the volumes of commercial vehicles are very low in comparison to passenger traffic. The travelling speed is 40 kph or less. In cases where commercial traffic is not envisaged such
as private access road in low cost housing area, the geometry standards could be lowered especially the lane width and gradient.
ACCESS CONTROL
Degree of Control
Access control is the condition where the right of owners or occupants of abutting land or other person to access, in connection with a road is fully or partially controlled by the public authority. Control of access is usually classified into three types for its degree of control, namely full control, partial control and non-control of access. a) Full Control of Access means that the preference s given to through traffic by providing
access connecting with selected public roads only and by prohibiting crossing at grade or direct private driveway connections. The access connections with public roads varies from 2 km in the highly developed central business area to 8 km in the sparsely developed urban fringes. b) Partial Control of Access means that preference is given to through traffic to a degree
that in addition to access connection with selected public roads, there may be some crossing trafficked. The spacing of at-grade intersections preferably signalized may vary from 0.4 km to 1.0 km. To compensate for the limited access to fully or partially access controlled roads, frontage or service roads are sometimes provided along side o f the main roads. c) In Non-Control Access, there is basically no limitation of access.
Selection of Access Control
The selection of the degree of control required is important so as to preserve the as-built capacity of the road as well as improve safety to all road users. Two aspects pertaining to the degree of control is to be noted. a) During the time of design in the consideration of accesses to existing developments. b) After the completion of the road in the control of accesses to future developments.
The selection of degree of access control depends on traffic volumes, function of the road and the road network around the areas.
DESIGN STANDARDS AND CRITERIA
Geometric Designs for Road Works
The Road design Standards and procedures adopted for the geometric design will be based on Jabatan Kerja Raya (JKR). General Summary Table of Geometric Design Criteria for Roads in Urban Areas shown in the JKR Arahan Teknik (Jalan) 8/86 (AT 8/86), ‗A Guide on Geometric Design of Roads‘ will be used for the design. All the values shown in the summary table are minimum or maximum values. All efforts should be made to achieve possible desirable values. The actual design values adopted for the roads should be more than the minimum requirements or less than the maximum requirements. Table below shows the geometric design criteria which were extracted from the AT 8/86 for the Minor Roads.
Element
Unit
Minor Road
Design Speed Lane Width Shoulder Width Shoulder Width (Structures > 100m) Median Width (Minimum) Median Width (Desirable) Marginal Strip Width Minimum Reserve Width Stopping Sight Distance Passing Sight Distance Minimum Radius Minimum Length of Spiral Maximum Super-elevation Maximum Grade (Desirable) Maximum Grade Crest Vertical Curve (K) Sag Vertical Curve (K)
km/h m m m m m m m m m m m Ratio % % -
40.0 2.75 1.5 0.5 N/A N/A 0.0 20.0 45.0 300 60 N/A 0.06 8 12 10 10
Design Speed
Design speed for the proposed road is 40 km/h. design speed is the maximum safe speed that can be maintained over a specific section of the road when conditions are so favorable that the design features of the road govern. The assumed design speed should be a logical one with respect to the topography, the adjacent land use and the type of road. Every effort should be made to use as high a design speed as practicable while maintaining the desired degree of safety, mobility and efficiency.
Horizontal Alignment
The alignment for roads will follow the road network as shown in the layout plan. Adjustments where necessary will be reviewed to suit topography and platform level of adjacent development areas in obtaining the desirable alignments and profiles of the roads and the locations and configuration of the intersections. The Table 2 of AT 8/86 shows the minimum radius to be adopted in urban areas for a particular design speed and a particular maximum super-elevation rate. The minimum radius to be adopted for a design speed of 40 km/h in urban area is 60 m. However, all efforts should be made to design curves with radii larger than th e minimum value for greater comfort and safety. The spiral lengths are normally calculated from the spiral formula or from the empirical super-elevation runoff lengths. The spiral length and super-elevation rate for the road for a particular design speed will be referred from the Table 3 of AT 8/86. The length of superelevation runoff shall not exceed a longitudinal slope of 1:200. However all efforts should be made to use longer spiral lengths than shown in the table. The maximum super-elevation rate will generally be adopted for the design of roads as specified in the Clause 4.2.2 of AT 8/86. The super-elevation rates gradually change along a curve of the road. A maximum super-elevation rate of 0.06 shall be adopted for the design. It is necessary to establish the proper relation between the design speed and curvature and also their joint relations with super-elevation and side friction in the design of horizontal curves.
The maximum rates of super-elevation usable are controlled by several factors such as climatic conditions, terrain features and frequency of slow moving vehicle. Table 2 shows the value of minimum radius for various design speed.
Table 2: Minimum Radius Design Speed
Minimum Radius (m)
km/h
e = 0.06
e = 0.10
120
710
570
100
465
375
80
280
230
60
150
125
50
100
85
40
60
50
30
35
30
20
15
15
Vertical Alignment
The maximum grade controls in terms of design speed were summarized in the Table 6 of AT 8/86. According to the above mentioned table the desirable maximum grade and the maximum grade for a particular design speed will be adopted. The desirable maximum grade is 4% and the maximum grade is 7%. The maximum grade used for the roads should be p[referable gentler than the maximum desirable grade. It was stated in the Clause 4.3.2 of At 8/86 that a desirable minimum grade of 0.5% should be used for better roadside drainage. It was further stated that a grade of 0.35% might be allowed where a high type pavement accurately crowned is used. Vertical curves are used to provide a smooth and gradual change between two intersecting tangent grades for comfortable and safe maneuvers. The length of a vertical curve (L) divided by the percentile algebraic difference in grades (A) is termed as k value which is used in
determining the horizontal distance from the beginning of the vertical curve to the apex of a crest curve or low point of a sag curve. Different k values will be used to determine the minimum lengths of sag and crest curves for various design speeds. The Table 4 and the Table 5 of AT 8/86 show the minimum k value for crest and sag curves respectively for various design speeds. However larger k values than the minimum should be used frequently in the establishment of vertical curves to ensure greater comfort and safety. The vertical profile of road affects the performance of vehicles.
Table 4 & 5: Minimum k value Design Speed km/h
100
80
40
30
20
Minimum k value (crest) 120
60
30 15 10 10
5
5
60
40
28
8
8
Minimum k value (sag)
120
60
50
15 12 10
Table 6: Maximum Grades Design Speed
Desirable Maximum Grade
Maximum Grade
km/h
%
%
120
2
5
100
3
6
80
4
7
60
5
8
50
6
9
40
7
10
30
8
12
20
9
15
RS R1a
10
25
The critical grade length indicates the maximum length of a designated upgrade upon which a loaded truck can operate without an unreasonable reduction in speed (refer Table 7). Three assumption were made to established the d esign value for critical grade: I. II.
The weight power ration of a loaded truck is 300 lb/hp. The average running speed as related to design speed is used to approximate the speed of vehicles beginning and uphill climb.
III.
Maximum reduction in speed to half the design speed is allowed for design speed of 80 km/h or above while for design speed of 50 and 40 km/h are 30 and 25 km/h respectively.
Table 7: Critical Grade Length Design Speed
Gradient
Critical Grade Length
km/h
%
m
120
3
500
4
400
5
300
4
500
5
400
6
300
5
500
6
400
7
300
6
300
7
250
8
200
7
250
8
200
9
170
8
200
9
170
10
150
100
80
60
50
40
Stopping Sight Distance
The stopping sight distance is the length required to enable a vehicle traveling at or near the design speed to stop before reaching an object in its path. The minimum stopping sight distance is acquired by the sum of the distance traversed by a vehicle from the instant the driver sights an object for which a stop is necessary, to the instant the brakes are applied and the required distance to stop the vehicle after the brakes application begins. Table 8 from the Arahan Teknik (Jalan) 8/86 shows the minimum stopping sight distance for various design speed.
Table 8: Minimum SSD Design Speed
Minimum SSD
km/h
m
120
285
100
205
80
140
60
85
50
65
40
45
30
30
20
20
Passing Sight Distance
Most roads in rural areas are two-lanes two ways on which vehicles frequently overtake slower moving vehicles, the passing of which must be accomplished on a lane regularly used by the opposing traffic. Passing sight distance for use in design should be determined on the basis of the length needed to safety complete a normal passing maneuver. The minimum passing sight distance for two-lane highway is determined as the sum of four distances: distances traversed during the perception and reaction time and during the initial acceleration to the point of encroachment on the passing lane; distance traveled while the passing vehicle occupies the passing lane; distance between the passing vehicles at the end of its maneuver and the opposing vehicle; and distance traversed by an opposing vehicle for two-third of the time the passing vehicle occupies the passing lane. Table 9 shows the minimum passing sight distance with various design speed.
Table 9: Minimum PSD Design Speed
Minimum PSD
km/h
120
800
100
700
80
550
60
450
50
350
40
300
30
250
20
200
Criteria for Measuring Sight Distance
There are two criteria applied in determining the sight the distance height of driver‘s eye where the eyes of the average driver in a passenger vehicle are considered to be 0.92 m above the road surface; and the height of the object where a height of 0.15 m is assumed for the measuring stopping sight distance and the height of object for passing sight distance is 1.32 m both measured from the road surface.
Combination of Horizontal and Vertical Alignment
Horizontal and vertical alignment should not be designed independently. They complement each other. Excellence in their design and in the design of their combination increase utility and safety, encourage uniform speed, and improve appearance, almost always without additional cost. There are several controls apply for proper combination of horizontal alignment and profile (vertical alignment):
I. II. III.
Curvature and grades should be in proper balance. Vertical Curvature superimposed upon horizontal curvature or vice versa. Sharp horizontal curvature should not be introduced at or near the top of pronounced crest vertical curve.
IV.
Sharp horizontal curvature should not be introduced at or near the low point of a pronounced sag vertical curve.
V.
On 2 lane roads the need for safe passing sections at frequent intervals and for an appreciable percentage of the length of the road often supersedes the general desirability for combination of horizontal and vertical alignment.
VI.
Horizontal curvature and profile should be made as flat as feasible at intersections where sights distance along both roads is important and vehicles may have to allow down or stop.
VII.
Variation in the width of median and the use of separate profiles and horizontal alignments on divided roads should be considered to derive design and operational advantages of one-way roadways.
Cross Section Elements
Pavement Surface
The selection of the pavement type is determined by the volume and composition of traffic, soil characteristic, weather, availability of materials, the initial cost and the overall annual maintenance throughout the service life cost. The important characteristic of surface type in relation to geometric design are the ability of a surface to retain the shape and dimensions, the ability to drain, and the effect on driver‘s behavior. Table 10 gives general selection of the pavement surface types for the various road standards.
Table 10: Pavement Surface Type Design Standard
Pavement Type
Description
R6/U6
H/H
Asphaltic Concrete/Concrete
R5/U5
H/H
Asphaltic Concrete/Concrete
R4/U4
I/H
Dense Bituminous Macadam/Asphaltic concrete/Concrete
R3/U3
L/I
Bituminous Macadam/Concrete
R2/U2
L/I
Surface Treatment/Semigrout
R1/U1
L/I
Earth Gravel/Semigrout
R1a/U1a
L
Surface Treatment/Semigrout
H: High Type Pavement I: Intermediate Type Pavement L: Low Type Pavement
Normal Cross Slope
Cross slope are an important element in the cross section design and a reasonably steep lateral slope is desirable to minimize water pounding on flat section of uncurbed pavement due to pavement imperfection or unequal settlements and to control the flow of water adjacent to the curb on curbed pavement (refer Table 11).
Table 11: Normal Pavement Cross Slope Surface Type
Cross Slope rate %
High
2.5
Intermediate
2.5-3.5
Low
2.5-6.0
Lane Width and Marginal Strips
Lane width and the condition of the pavement surface are the most important features of a road pertaining to the safety and comfort of driving. The capability of a highway is markedly affected by the lane width and in capacity sense; the effective width of a traveled way is further reduced when adjacent obstructions such as retaining walls, bridge piers and parked cars restrict the lateral clearance. Marginal strip is a narrow pavement strip attached to both edge of a carriageway. It is paved to the same standard as the pavement structures. The marginal strip is included as part of the shoulder width and is demarcated from the through lane by lane edge markings on the marginal strip. Table 12 shows the dimension for lane width and marginal strip for various roads standard.
Table 12: Lane and Marginal Strip Width Design Standard
Lane Width
Marginal Strip Width
m
m
R6/U6
3.50
0.50
R5/U5
3.50
0.50
R4/U4
3.25
0.25
R3/U3
3.00
0.25
R2/U2
2.75
0.00
R1/U1
(5.00)
0.00
R1a/U1a
(4.50)
0.00
(): Denotes the total two-way lane width
Shoulder
A shoulder is the portion of the roadway continuous with the traveled way for accommodation of stopped vehicle, for emergency use and for lateral support of the pavement. The normal usable shoulder width that should be provided along high type facilities is considered 3m. However, a minimum usable shoulder width of 0.6m should be considered in cases where the usable width is not feasible like in difficult terrain and on low volume roads. All shoulder should be sloped sufficiently to rapid drain surface water but not to the extent that vehicular use would be hazardous. Because the type of shoulder construction has a bearing on the cross slope, the two should be determined jointly. Bituminous surface shoulder should be slope from 2 to 6 percent. Table 13 shows the dimension for road shoulders.
Table 13: Shoulder Width Design Standard
Usable Shoulder Width (m)
(Rural)
Terrain Flat
Rolling
Mountainous
R6
3.00
3.00
2.50
R5
3.00
3.00
2.50
R4
3.00
3.00
2.00
R3
2.50
2.50
2.00
R2
2.00
2.00
1.50
R1
1.50
1.50
1.50
R1a
1.50
1.50
1.50
Design Standard
Usable Shoulder Width (m)
(Urban)
Area Type I
II
III
R6
3.00
3.00
2.50
R5
3.00
3.00
2.50
R4
3.00
2.50
2.00
R3
2.50
2.00
1.50
R2
2.00
1.50
1.50
R1
1.50
1.50
1.50
R1a
1.50
1.50
1.50
PAVEMENT DESIGN
A layered flexible pavement structure consists of sub-bas course, base course, dense bituminous macadam, binder course and wearing course. The minimum thickness of each layer will be derived for the structural stability of the pavement to cater the forecasted traffic flow for a specified design period. The thickness of layers will be based on the design California Bearing Ratio (CBR) of the sub-grade material and the design total equivalent standard axles (ESA). The
pavement will be designed for a design period of 10 years with provision of strengthening the pavement by overlay after ten years.
TRAFFIC CONTROL DEVICES
Signing and markings are directly related to the design of the road and are features of traffic control and operation that must be considered in the geometric design of highway. The signing and marking should be designed concurrently with the geometric as an integral part, and this will reduce significantly the possibility of future operational problems.
Road Marking
Road Marking and delineation are used to regulate traffic or to warn or guide road users. They may be used either alone or to supplement other traffic control devices. Road marking shall be uniform in design, position and application to enable them to be recognized and understood immediately by road users. Markings which must be visible at night shall be reflectorized unless ambient allumination assures adequate visibility. All markings on high ways shall be reflectorized. Even on well-lighted town and streets it is generally desirable that markings which must be visible at night reflectorized. Road pavement may be marked by one or more of the following materials: I. II. III.
Paint. Thermoplastics. Preformed Tapes.
Traffic Signs
The purpose of traffic signs is to help to ensure the safe and informed operation of every road user on the highways. Traffic signs are to regulate, warn, or guide road users. They are essential where special regulations apply at specific times only or where hazards are not selfevident. They also give information as to highway routes, directions, destinations and places of
interest. The critical factors in meeting the greatest efficiency of traffic signs are color, shape and size used, layout of its face, its position and illumination or reflectorization.
Traffic Signals
Traffic control signals are devices that control vehicular and pedestrian traffic by assigning the right of way to various movement for certain pretimed or traffic actuated interval of time. They are one of the key elements in the function of many urban roads and should be integrated with the geometric design so as to achieve optimum operational efficiency.
INTERSECTION
Intersection is located where two or more through road come across each other. The main consideration in designing a junction is the turning radius of vehicle. Turning at junction should be designed to accommodate such turning radius of vehicle for easy movement of the vehicle without causing any hazards to the opposing vehicle at the junction. The summary of vehicle dimension for design consideration is shown in Table 14. Detail design of junction should be referred to Arahan Teknik 11/87.
Table 14: Design Vehicle Dimensions Design Vehicle Type
Passenger
Symbol
Dimension (m) Wheel
Overhang
Turning
Overall
Overall
Height
Radius (m)
Base
Front
Rear
Length
Width
P
3.4
0.9
1.5
5.8
2.1
1.3
7.3
SU
6.1
1.2
1.8
9.1
2.6
4.1
12.8
WB-50
7.9
0.9
0.6
16.7
2.6
4.1
13.7
Car Single Unit Truck Truck Combination
Relocation of Services
The consulting Engineer shall make a survey of the existing utility services and lialise closely with the authorities concerned on the proposed future relocation of such services. The Engineer shall put up detailed plans and proposals for the relocation of these services if affected by the proposed work.
HYDROLOGICAL STUDIES AND DRAINAGE DESIGN
Road drainage facilities provide for carrying water across the right of way and for removal of storm water from the road itself. These facilities include bridges, culverts, channels, gutters and various types of drains. Drainage design considerations are an integral part of geometric design and flood plain encroachments frequently affect the highway alignment and profile. The cost of drainage is neither incidental nor minor on most roads. Careful attention to requirements for adequate drainage and protection of the highway from floods in all phase of location and design will prove to be effective to reducing costs in both construction and maintenance. In general, references shall be made to ‗Urban Stormwater Management Manual for Malaysia‘, which published by the Department of Irrigation and Drainage of Malaysia.
ROADWAY LIGHTING
Proper application of the fixed lighting principles and techniques shall be used to ensure that visibility provided on the roads will provide economic and social benefits to the public which includes: I. II.
Reduction in night accidents and attenuate human misery and economic loss. Aid to police protection.
III.
Facilitation of flow of traffic.
IV.
Promotion of business and industry, during night hours.
V.
Inspiration for community growth.
ENVIRONMENTAL IMPACT ASSESSMENT FOR ROAD PROJECTS
Introduction
Like people, most organizations are heavily dependant on roads to distribute their goods & to carry their executives and sales people. Yet, though once seen as the engine of progress, roads are facing increasing criticism around the world. A road is a main road for travel by the public between important destinations, such as cities, large towns, and states. Road designs vary widely and can range from a two-lane road without margins to a multi-lane, grade-separated expressway, freeway, or motorway. Impact due to construction of roads include the noise and dust from construction, the use of non-renewable aggregates, the loss of natural habitats and green space and increase in traffic (with all its impacts). The best practice is to undertake an environmental impact assessment (EIA) before the road is designed. Environmental Impact Assessment (EIA) is defined as ―the process of examining the environmental effects of the development - from consideration of the environmental aspects at design stage, through to the preparation of an Environmental Impact Statement, evaluation of the EIS by a competent authority and the subsequent decision as to whether the development should be permitted to proceed, also encompassing public response to that decision‖.
The EIA methodology promotes a practical and dynamic process of environmental protection that allows significant adverse impacts to be avoided or mitigated throughout the entire planning and design process. Road planning and design is an iterative process where planning and design evolve in response to environmental and other considerations. This ensures that environmental considerations become an integral part of the overall route corridor selection and road scheme planning and design process.
Anticipated Impacts Due to Road Construction Project
Encroachment on precious ecology
The proposed routing of the road encroaches upon precious ecological resources, including forests and swamps. This also disturbs the natural habitats of a lot of creatures and animals leaving on the encroach land. The ecological disturbance is likely to occur. The construction activities will drive some wildlife away from their habitats, particularly migratory birds. The construction period will last for quite a long time (3-4 years) and many migratory birds within about 500 m of the proposed expressway will leave their currently roosting and feeding places and move away. During road construction, the vegetation on the acquired land will be destroyed, and the local ecosystem is changed. In addition, the destruction and fragmentation effect of the road construction may diminish the habitats for some of the animal species, so that there may not be enough roosting places any more for them to survive. During operation, the traffic noise, traffic lights at night and vehicle emissions may cause some adverse impacts on the wildlife around the road.
Adverse impact on historical/cultural monuments
The nearby structures to road projects are adversely affected due to the pollution and environmental disturbances created by the project. During the construction phase, huge amount of CO2 (Carbon Dioxide) and CO (Carbon Monoxide) gases are released into the atmosphere. The gas poses a threat to ancient monuments as they are made up of lime which reacts with these gases in presence of water/moisture.
Impairment of fisheries/ aquatic ecology and other beneficial water uses
The water bodies like lake, pond or river which are close to the road site get affected by the construction activity. The workers and staff living near to the site uses the water from these water bodies and in turn pollute them causing harm to aquatic ecology. The rain water may wash away the chemicals and other hazardous product to the water body affecting the oxygen content of it. This will lead to impairment of fisheries.
Water quality
The Project will involve the construction of small and large bridges, which will be built with hollow piers and deep foundations with bored piles. The pile drilling operation will generate a great amount of spoil of water. Major sources of potential water pollution were identified as I.
Increased soil erosion during construction, which may cause water pollution with sedimentation.
II.
Wastewater pollution caused by large construction sites, in particular bridge construction.
III.
Potential pollution associated with the construction of bridge foundations with bored piles.
IV.
Pollution caused by surface runoff and service area wastewater.
Water quality impacts due to construction sites
Wastewater and hazardous materials (fuel, oil, acids, caustics, etc.) may drain into streams and drainage areas, causing pollution to surface water or groundwater. This is particularly true for large construction sites, construction campsites, and staging areas where workers, construction equipment, and building materials are most con centrated. a) Expressway Runoff: Rainwater washes out atmospheric pollutants, picks up roadway deposits, and runs off into rivers. The impact of the initial runoff pollutants on the water quality b) Wastewater Effluent from the Service Area: There will be fuelling and service stations as well as offices, hotels, and restaurants for the passengers in the service
area. Sanitary wastewater effluent from these facilities as well as wastewater generated by car washing, maintenance, and repair operations will be generated.
Erosion and Siltation
The wearing away, detachment and transportation of soil from one place to another place and its deposition by moving water, blowing wind or other causes is called soil erosion. Large numbers of trees and plantation has to be removed for construction of road. This leads to loosing of the soil, soil disturbance, and exposure of bare soil surface. This causes problem of soil erosion and siltation during rain or heavy wind. The most severe problems will be associated with embankment construction in the plain area, road sections with heavy cuts and fills, borrow and spoil sites, as well as bridge and culvert construction sites, particularly on rainy days.
Environmental aesthetics
Roads project involves cutting of trees, soil filling and cutting operation. This disturbs the natural aesthetic of the environment (scenic value). Some expressway components like large bridges and interchanges will create visual impacts and detract from the natural beauty of the area. The lack of resurfacing/ replanting of exposed areas are also the leading factor to aesthetic reduction.
Noise and Vibration
During the construction stage massive equipments like excavators, power shovels, dumpers, compacters, loader etc are used. This causes considerable vibrations in nearby areas. They also produce high noise levels. This all disturbs the natural surroundings and creates unfavourable conditions for the living creatures. The vibrations may affect the structures nearby.
Air pollution hazards
The project results in discharge of air pollutants from machines and motor vehicles, especially carbon monoxide, which under adverse conditions could cause severe air pollution hazards to nearby area and communities. a) Air Quality Impacts during Operation
If project area is a non-attainment area for TSP and CO, with their background concentrations well exceeding the applicable air quality standards. The vehicle emissions and fugitive dust emissions from the expressway will add to the problem. b) Air Quality Impacts during Construction
Construction activities particularly earthworks; increased traffic and the use of cement, asphalt, and other building materials will produce excessive airborne dust and toxic asphalt fumes, causing a major impact on air quality within the project area. It was observed that the TSP concentration at a distance 50 m to the leeward of a concrete mixing plant can be 1.368 mg/Nm3, & 0.619 mg/Nm3 at 100 m.
Road run-off pollution
Surface runoff from roads may contain sufficient petroleum drippage plus spilled material (including toxic and hazardous materials) which can adversely affect aquatic ecology and environmental aesthetics.
Effect on Natural resources
The Project will disrupt some existing irrigation systems, particularly in the plain areas where the road will be constructed on filled-up embankment. This fragmentation will also affect the existing flood-relief channels and natural drainage of th e area.
Land Acquisition o
The loss in agricultural products due to farm land decrease
o
Another extra land is needed during the construction period for temporary use (construction camp sites, staging areas, access roads, borrow and spoil sites, etc.)
o
Some buildings will be demolished and wire poles will be removed, and one small enterprise may be moved.
Remedies
The environmental impact caused due to road project can be reduced by adopting following measures: o
Removing only the necessary vegetation; applying for permits to cut down trees. Revegetation of green areas.
o
Make up embankments. Disposal of surplus earth. Disposal of waste (Plan for processing solid and liquid waste).
o
Performing of the cultural heritage protection plan. Covering or dampening uncovered soils.
o
Green areas, ornate. Maintenance. Soil protection. Water protection.
o
Wastewater effluents from the service area will be treated by a chemical and biological treatment system in accordance with applicable standards before discharge into the nearby irrigation system.
o
To minimize the visual impacts, the following measures will be taken:
Minimize cut and fill slopes where possible and, in particular, avoid steep cut slopes;
Implement site-specific landscaping and re-vegetation on both sides of the road, all cut slopes, and disturbed land, making the expressway a beautiful green corridor; and
Design bridges, interchanges, and do their infrastructure in such a way as to achieve consistency with the surrounding natural landscape, local buildings, and facilities in terms of form, colour, and texture.
o
To minimize the nighttime noise impacts, noise suppressors will be used on construction equipment where feasible. High noise machinery will not be allowed to operate in the proximity of a school when classes are in session, and also from 22:00 to 6:00 hrs when there are residential areas nearby.
o
Establish greenbelt between the road and the villages and school to reduce noise level and air pollution during operation.
o
To minimize the dust impact, construction fields and major access roads and haul roads will be watered on a set schedule, particularly in the dry season. Construction materials storage and concrete mixing plants will be sited more than 100 m away, and asphalt
mixing plants 300 m away in a downwind direction from residences and schools. All the mixing equipment will be closed systems with dust extractors.
NECESSITY OF QUALITY ASSURANCE
The main objectives of road construction are to provide a comfortable and save facility to the public particularly to the road user. With the h uge amount of money spent for the construction of new roads, the understanding of necessity of achieving required construction quality is very much crucial in order to ensure the structural and the functionality of the constructed roads or facilities last within design life. In Malaysia, the quality assurance in the road construction very much covered at all level i.e. beginning from the planning design and construction as well as during maintenance stage. For instant, the requirement of having a proper planning is very important i.e. the road authority must carry out proper detail study on the proposed location in terms of overall event or development nearby as well as development of other agencies like housing and business that will link to the new proposed construction road. Ideally in the design stage, the designer will consider all necessary aspects of the road geometry and structure of the pavement that comply with the approved design guideline, specification or technical notes. Upon compliance to these documents, the confident level of producing high quality of road will be achieved. But at certain circumstances i.e. budget constraint, certain criteria in the design especially which is related to the geometry has to be left out or compromised. This compromisation should be done carefully in order to avoid occurrence of lacking of safety aspect of the particular road. Quality assurance during construction considered to be the most critical part in whole cycle of road construction. The compliance to specification must be assured by competent officer. Selection of good and experience contractor and consultant also the main factor that contributing to the quality product. The sense of responsibility toward producing good quality of road by all the project team will ensure production of the top class road. It is not an easy task
because sometime outside influences such as political influence will affect the output quality of new constructed as well as in maintenance of existing road.
SUSTAINABLE DEVELOPMENT ON ROAD Introduction
Roads perform an important connecting function for the community. While roads are important transportation and communication links, there are some concerns about their sustainability aspects. In particular, while roads have both economic and social benefits, there is concern about their impact on the natural environment. The main environmental issues with roads tend to revolve around greenhouse gas emissions from the traffic the carry. They also have potential environmental and social effect, such as their ability to impact on natural landscape and on those who live near them. However, it is possible to construct and manage roads in an environmentally and socially responsible manner. Another aspect of road sustainability is that roads, as a significant component of the transportation fabric of society, should be available for as much time as possible. In particular, major routes should wherever possible. If they are not, essential goods may not be able to be transported and there is significant impact on the economy. Such an example, if flood disaster happen, some major transportation routes were unable to be used both during and for some time after being flooded, with consequent social and economic effect. Given the tension between the environmental impacts of roads and their importance in modern society, road authorities and governments have provided guidance on the planning, development and operation of roads in sustainable manner.
The Relationship between the Road and Its Environment
To better understand the issues in sustainable roads, it is firstly important to understand the concept of sustainability, and then to understand how roads are interact with their environments and communities.
The concept of sustainability used is based on the well-known definition of sustainable development used by Brundtly (1987), which is ―meeting the needs of the present without compromising the ability of future generations to meet their own needs.‖ Such sustainability, as commonly understood, has three components, all of which require to be kept in balance – economic sustainability, social sustainability and environmental sustainability. Thus, while from an economic viewpoint roads are required to be built and managed to a budget and provide economic benefit, it is also necessary to consider their impact on society and the physical environment.
Factors in The Construction of Sustainability Roads
The construction and management of a sustainable road therefore requires consideration of a number of factors related to both legislative requirements and good sustainable management practices. Some of the factors in this process, as related to construction and management of the road, are described below.
Road Material Selection and Use
It is important to minimize the embodied energy in road construction and maintenance materials. For example, consideration should be given to the selection, subject to their suitability, of locally occurring materials for aggregates, in order to reduce embodied energy of the transportation effort of importing material onto the construction site.
Minimizing embodied energy is enhanced by the use of recycled materials and the recycling of pavement and surface materials during road rehabilitation or replacement. The use of recycled aggregates is quite common and recycled glass has also been used for road or pathway pavement. As with all materials, caution is required in using recycled materials. However, provided the materials for recycling are selected with care and knowledge about their advantages and disadvantages, judicious reuse of selected materials can lead to substantial embodied energy savings and decrease waste.
Planning and Design
This part defines the parameters of the road development, and also specifies the construction parameter. Sustainable planning and design may lead to reduce energy use, sustainable management of resources and waste management. Design also impacts on items like material selection and pavement design. An important consideration from the social aspect of sustainability is safety in design. Such an example, a designer has an obligation to minimize risks in the design of a structure so that the design does not adversely affect the workplace health and safety of person either during or post construction. This requirement has implications for the whole road life cycle. Finally, one important consideration in both design and construction is ensuring quality of materials and construction processes. Control of variability (such as in the properties of materials) will contribute to improved and more predictable outcomes for the road over its life cycle.
PARKING
1.0
INTRODUCTION
Parking system is one of the branches of engineering and it is one of the duties of the Traffic Engineer. Parking is important to be aware of the study if they are adequate for current needs or otherwise. Parking can be defined as a placement or storage area for vehicles that do not move and turned off the engine in an area. It is a convenience to drivers parking or storing vehicles to run their own affairs. Parking density can be measured in the vehicle per region area or vehicles per length of road. Parking facilities is the key in providing a planning and control of traffic and is a cornerstone in providing perfect transport policy in the area. Development and rapid progress in the area will result in the traffic systems to increase and indirectly will result in demand for parking requ irement also increase. In a study of parking system, we need to know the actual problem, the existing facilities suitable or not, the impact on traffic and the impact on the environment must be considered in the evaluation of car placement problem. Besides that, to studies on the movement of vehicles and stopping vehicles study is also very important.
2.0
THE IMPORTANCE OF PARKING SYSTEM
Parking systems should be provided for the public to park their cars easily and safely. Parking facilities provided must have security control so that drivers do not have to worry about their car left in the parking lot. There is no doubt about the importance of parking in line with the increase in car use at present. The authorities need to provide every parking area or building that caught the attention of people or groups of people regardless of whether they are located in urban or rural areas. For example, areas such as colleges and universities, hospitals, stadiums, shopping malls, offices and others.
Lack of parking will lead to congestion and provide good scenery as well as other pollutants such as noise and air. This also can lead to economic wastage because they have to spend more in terms of fuel consumption. Provisioning of adequate parking can meet the demand coming from the drivers especially during peak times. This will help to avoid traffic congestion on the roads. Parking that was not able to meet the needs and demands of the driver will cause the movement of cars on the road will become increasingly slow and crowded due to the increasing number of cars. This will resulted in the least saturated flow of the road. So, in order to avoid the traffic congestion on the roads, the provision of adequate parking is requ ired.
3.0
STUDIES METHODS OF PARKING SPACES
Studies method was carried out on the parking spaces are intended to ensure the effectiveness of the parking space and also to get the number of required parking spaces. Provision of car parking spaces depend on the economic and social factors in which the studies to be carried out. Most of the parking spaces demand in large and medium cities required high demand and usually the management cannot meet the demand. Among the problems that hinder the smooth planning of parking spaces in effective are:
a) Increase the number of people in the future for the area. b) Levels of car ownership in the design. c) The number and rate of travel individually. d) Daily trip rate prevailing during normal daily travel time and peak travel times. e) Number of load road leading to the area of studies. f) The relationship between the amount of manual focus peak period parking space with parking space overall. g) Parking period for different categories of parking space users. h) The time considered for planning purposes. i) Increase the floor area of the study area is cu rrently under construction. j) Change attraction of the area concerned after development.
Details of the above have to be taken seriously to get a more realistic assessment and more accurate decisions. With the right decision needs of parking space demand in the future can be minimized. Total parking spaces required is d irectly proportional to the increase in population and the development of the study area.
4.0
PARKING PLACING
Placement of parking is also an important thing in planning development in the area. Traffic study process and the use of land and parking study can provide guidance for us to provide the required parking for either short term or long term. Car parking provision were based on the car at the time of peak volume and the number of cars on the road overall. Provision of adequate parking will avoid the occurrence of congestion in the parking lot and also encourage the car driver to park their cars in places that prohibited for them. Traffic congestion in Bangi is increasing rapidly as development of the city. Therefore, the necessary control measures were made to ensure the car park is sufficient to cover the high traffic volume.
Therefore, placement of parking must be made by looking at the things that affect concentration to an area of the vehicle to ensure they are working and effectively functioning to the public, hence, it will be able to avoid traffic congestion and environmental pollution.
5.0
TYPES OF PARKING
There are many types of car parks that can be obtained in the traffic system. Type of parking can be classified into two, namely: 1. Parking on the street area. 2. Parking on the off street area.
5.1
Parking on the Street
Provision of car parking on the street can be built either on one side or both sides of the road to suit the road. Car parking provision of this kind is usually performed in the street which contains few vehicles and the demand is low. This type of parking can be controlled by limiting the duration of car placement. It can be done in several ways as follows: a. By using parking meters. b. Setting a specific time for parking in an area that is critical c. Setting up the area parking lot.
5.1.1
Metered Parking
There are many types of car parking like this available in a city which had higher percent of traffic. This method was introduced by the Well in 1969. An urban area can be designed as all the forbidden zone of parking meters, except in the marked car lots. In this method there are some good among them are: -
a. Placement of the car can be easily adjusted. b. Car placement period will be reduced. c. Parking areas clearly marked and drivers will continue to monitor that it does not place elsewhere. d. Payment imposed promoting private enterprises providing off-road parking to the saving public funds.
5.1.2 Tape Parking
This type of parking was an over-riding alternative to metered parking. This method scheme offers free parking driving along an unmarked curb on the designated times. When the driver enters the zone scheme he will find a car park and display the tape in his car mirror. The benefit from this method is that there are no installation capital costs but there are some disadvantages of this method such as: a) No results were released. b) Need more traffic officers. c) Drivers on the tour difficult to get the tape.
5.2
Parking on the Off-Street Area
The Provision of this type of parking was made to reduce the concentration of drivers to parking on the street only. In this way it can reduce traffic congestion on the road. The placement this type of parking must be appropriate and strategic to facilitate the people to conduct their business. To facilitate the entry and exit of vehicles, the entry and exit lanes should be designed gently so that it can provide comfort to the car park users. Maintenance and the arrangement are usually conducted by local authorities or private companies.
5.2.1 The Surface Parking
This type of parking is the most famous among the types of off-street parking. It uses a lot of land. So it requires a perfect design, alwa ys controlled and cleaned.
5.2.2
Multi-Storey Car park Building
This type was popular in urban areas. This type of parking reduces land use. Normally this type of parking is available near the offices, hotels and shopping malls in the city center and is usually conducted by private companies that have a building. Payment will be charged to drivers who park their vehicles on parking duration. Multi-storey car park building can be classified into 3 groups: a) Attendance parking. b) Car park users c) A combination car park users and attendance parking
5.2.3
Underground Car Park
Most of this type of parking is usually available at the bottom of the building, offices, shopping centers, under the road, public park or community center. The cost of this type of parking construction is expensive and perhaps this type is the most expensive parking lot. Therefore, in most underground parking part of the initial cost will be offset because it represents the costs which would have existed e ven if parking is not built. Drivers who park in this area usually will be charged and this will reminds them not to park too long in this parking lot. This is a way to controlling the parking area to reduce congestion in the affected areas.
5.2.4
Roof Top Car Park
Rooftop parking provides parking at a reasonable cost. Major trip was to ram the increased expense in proportion to the height of the building. In some cases it is possible to connect two or more to allow the ram in and out for the entire area.
5.2.5
Ram Parking System
This type of parking is one of the types of off-street parking. It is usually built in shopping centers, supermarkets and hotel buildings.
6.0
PARKING STANDARDS
Provision of car parking in development planning carried out by the authorities must be based on specific standards according to the importance of certain areas. This is means that they must provide parking to drivers that can operate without control over them. In residential areas and rural areas, the policy should be implemented so that drivers have access to a convenient parking. This means that proper planning should be made to streamline the parking area and the total number of cars at peak times. Thus the control of parking should be made by the authority that manages the affected areas. Parking should be used by the public if there is a demand for it. The policy is to allow people to park their cars, especially in certain areas.
6.1
The purpose of Parking Standards
The importance of providing standards for the p arking is intended: -
a. To ensure that the parking areas are sufficient to cater for the placement of cars available at one area. b. To avoid road congestion due to excessive number of cars in parking lots provide a more orderly. This will sustain the environment.
Parking standards are made is different and distinct from one place to another place. This is due to the different demands of parking between the areas involved. Others, these standards are based on the total number of cars in the area. The area that has the status of progressing and different interests will lead to the number of cars in the areas to be different. This difference is seen in the parking demand requirements for operation and non-operating.
6.2
Parking Specification
Specification for car parking is necessary to determine the number of parking spaces to an area. It should be made to ensure that parking is available to operate at optimum levels for each car. The space needed for parking can be seen in the table below.
Types of Building
Residential Area
Parking
Occupant: 1 Visitor: 1
Shop Area
Occupant: 1 2
Visitor: 1 for every 25m shop area Office Area
Occupant: 1 for every officer and 4 for employees Visitor: 10% of the parking spaces for employees
Bank Area
Occupant: 1 for each of the officers and 4 other
employees Industrial Area
Occupant: 1 for every 25 m of industrial areas Visitor: 10% of parking for employees
Public Library
Occupant: 1 for every 3 employees on duty Visitor: 3 for each 500 members and 1 addition for every 10 seats
Hospital
Occupant: 1 for every doctor and 1 unit every other employee Patient & Visitor: 1 for each 3 beds
School
Occupant: 1 for every 2 employee Visitor: 4 for every 1000 students
Higher Educational Institute
Occupant: 1 for every 2 employees in duty Visitor: 5 for every 1000 students
Museum and Art Gallery Centre
Occupant: 1 for every 2 employees in duty 2
Visitor: 1 for every 30m area Cinema
Occupant: 1 for every 3 employees in duty Visitor: 1 for every 5 seats
As we can see from the table above for school occupancy for one parking lot for every two employees or teachers and four parking lot for every one thousand students. In this project we will overall provided 39 parking lots for ever y teachers, staffs and visitors.
7.0
PAVEMENT DESIGN CONSIDERATION FOR PARKING LOT
7.1
Drainage Provisions
Drainage problems are frequently a major cause of parking area pavement failures. This is especially the case with irrigation sprinkler systems located in parking lot islands and medians. It is critical to keep water away from the subgrade soil. If the subgrade becomes saturated, it will lose strength and stability, making the overlying pavement structure susceptible to breakup under imposed loads
Drainage provisions should be carefully designed and should be installed early in the construction process. As a general guideline, parking area surfaces should have minimum slope guidelines. The parking lot should be designed to provide for positive drainage. Pavement cross slopes of less than 2 percent hard to construct without the formation of ―bird bath‖, slight depressions that pond water. They should also be constructed so water does not accumulate at the pavement edge. Runoff should be collected in curb and gutter pans and channeled off of the parking lot. Curb and gutter cross sections should be built so that water flows within the designed flow line and not along the interface between the asphalt pavement and curb face. Areas of high natural permeability may require an under drain system to carry water away from the pavement substructure. Any soft or spongy area encountered during construction should be immediately evaluated for under drain installation or for removal and replacement with suitable materials.
7.2
Subgrade Preparations
All underground utilities should be protected or relocated before grading. All topsoil should be removed. Poor quality soil may be improved by adding granular materials, soil stabilization, or other mixtures to stabilized the existing soils. Laboratory tests are recommended to evaluate the load supporting characteristics of the subgrade soil and determination, the applicability for stabilization or modification due to the presence of sulfate should be considered. The area to be paved should have all rock, debris, and vegetation removed. The area should be treated with a soil sterilant to inhibit future vegetative growth. Grading and compaction of the area should be completed so as to eliminate yielding or pumping of the soil. Proof rolling is recommended prior to application of the base layer. The subgrade should be compacted to a uniform density of 95 percent of the maximum density. This should be determined in accordance with Standard or Modifier Proctor density as appropriate to the soil type. When finished, the graded subgrade should not deviate from the required grade and cross section by more than one half inch in ten feet.
7.3
Untreated Aggregate Base Construction
The untreated aggregate base course section based on the pavement design should consist of one or more layers placed directly on the prepared subgrade, with or without a separation fabric, depending on soil type. It should be spread and compacted with moisture control to the uniform thickness, density and finished grade as required on the plans. It should be noted that an untreated aggregate base might be sensitive to water in the subgrade. Pavement failures associated with water in the subgrade are accelerated if an untreated base allows water to enter the pavement structure. Grading should be done to promote natural drainage, otherwise, other types of under drain s ystems should be included in the design.
7.4
Prime Coat
An application of low viscosity liquid asphalt may be required over untreated aggregate base before placing the HMA surface course. A prime coat and its benefits differ with each application, and its use often can be eliminated. Discuss requirements with the paving contractor. If a prime coat is used, AEP (Asphalt Emulsified Prime) should be specified as it is designed to penetrate the base material. The use of a tack coat is not recommended for use as a prime coat.
7.5
Hot Mix Asphalt (HMA)/Warm Mix Asphalt (WMA) Base Construction
The asphalt base course material should be placed directly on the prepared subgrade in one or more lifts. It should be spread and compacted to the thickness indicated on the plans. Compaction of this asphalt base is one of the most important construction operations contributing to the proper performance of the completed pavement. This is why it is so important to have a properly prepared and unyielding subgrade against which to compact. The HMA base material should meet the specifications for the mix type specified.
7.6
Tack Coat
Before placing successive pavement layers, the previous course should be cleaned and a tack coat of diluted emulsified asphalt should be applied. The tack coat may be eliminated if the previous coat is freshly placed and thoroughly clean.
7.7
Hot Mix Asphalt (HMA)/Warm Mix Asphalt (WMA) Surface Course
Material for the surface course should be an HMA or WMA mix placed in one or more lifts to the finished lines and grade as shown on the plans. The plant mix material should conform to specifications for Hot or Warm Mix Asphalt. Warm Mix Asphalt is a relatively new technology whereby production and construction temperatures of asphalt concrete mixtures are significantly o
reduced (50-100 F) via foaming of the asphalt binder or chemical additive. In either case, fumes and emissions are significantly reduced. From a design perspective, current recommendations are to conduct the asphalt mixture design in accordance with established procedures for HMA and then verify the WMA mixture properties during production. For most application, the finished asphalt surface should not vary from established grade by more than one-quarter inch in ten feet when measured n any direction. This requirement may not be attainable when matching curb, gutter and V-pans. Any irregularities in the surface of the pavement course should be corrected directly behind the paver. As soon as the material can be compacted without displacement, rolling and compaction should start and should continue until the surface is thoroughly compacted and roller marks disappear.
8.0
Structural Design of Interlocking Concrete Pavement for Roads and Parking Lots
8.1
History
The concept of interlocking concrete pavement dates back to the roads of the Roman Empire. They were constructed with tightly fitted paving units set on a compacted aggregate base. The modern version, concrete pavers, is manufactured with close tolerances to help ensure interlock. Concrete pavers were developed in the Netherlands in the late 1940‘s as a replacement for clay
brick streets. A strong, millennia-old tradition of segmental paving in Europe enabled interlocking concrete pavement to spread quickly. It is now established as a conventional means 2
2
of paving there, with some two billion ft (200 million m ) installed annually. Concrete pavers came to North America in the 1970‘s. They have been used successfully in numerous residential, commercial, municipal, port and airport applications.
8.2
Advantages
The paving system offers the advantages of concrete materials and flexible asphalt pavement. As high-strength concrete, the units have high resistance to freeze-thaw cycles and deicing salts, high abrasion and skid resistance, no damage from petroleum products nor from concentrated point loads or high temperatures. Once installed, there is no waiting time for curing. The pavement is immediately ready for traffic. Stress cracking and degradation of the surface is minimized because the numerous joints, or intentional ―cracks,‖ act as the means for load transfer. Like flexible asphalt pavement, an aggregate base accomodates minor settlement without surface cracking. An aggregate base facilitates fast construction, as well as access to underground utilities. Mechanical installation of concrete pavers can further shorten construction time. Pavement reinstatement is enhanced by reusable paving units, thereby reducing waste materials.
8.3
The Principle of Interlock
Interlock is critical to the structural performance of interlocking concrete pavement. When considering design and construction, three types of interlock must be achieved: vertical, rotational, and horizontal interlock. These are illustrated in Figure 2. Vertical interlock is achieved by the shear transfer of loads to surrounding units through sand in the joints. Rotational interlock is maintained by the pavers being of sufficient thickness, placed closely together, and restrained by a curb from lateral forces of vehicle t ires. Rotational interlock can be further enhanced if there is a slight crown to the pavement cross section. Besides facilitating drainage, the crown enables the units to tighten slightly
through loads and minor settlement across the entire pavement, thereby increasing structural capacity. Horizontal interlock is primarily achieved through the use of laying patterns that disperse forces from braking, turning, and accelerating vehicles. The most effective laying patterns for maintaining interlock are herringbone patterns. Testing has shown that these patterns offer greater structural capacity and resistance to lateral movement than other laying patterns (1, 2, 3). Therefore, herringbone patterns are recommended in areas subject to vehicular traffic. See Figure 3. Stable edge restraints such as curbs are essential. They maintain horizontal interlock while the units are subject to repeated lateral loads from vehicle tires. ICPI Tech Spec 3, Edge Restraints for Interlocking Concrete Pavements offers guidance on the selection and detailing of edge restraints for a range of applications.
8.4
Typical Pavement Design and Construction
Figure 4 illustrates typical schematic cross sections for interlocking concrete pavement. Both the base and subbase are compacted aggregate. Many pavements for city and residential uses do not require an aggregate subbase except for very heavy use, or over a weak soil subgrade. In these situations it may be more economical to use asphalt or cement stabilized base layers. They are often placed over a subbase layer of unbound compacted aggregate.
Construction is covered in ICPI Tech Spec 2, Construction of Interlocking Concrete Pavement. The steps for preparing the soil subgrade and base materials are similar to those required for flexible asphalt pavements. After the base surface is built to specified elevations and surface tolerances, bedding sand is screeded in an even layer, typically 1 – 11/2 in. (25 – 40 mm) thick. The units are placed, manually or mechanically, on the smooth bedding sand, constrained by stationary edge restraints. The pavers are vibrated with a high frequency plate vibrator. This action forces sand into the bottom of the joints of the pavers and begins compaction of the bedding sand. Sand is then spread and swept into the joints, and the pavers are compacted again until the joints are filled. Complete compaction of the sand and slight settlement of the pavers tightens them. During compaction, the pavement is transformed from a loose collection of pavers to an interlocking system capable of spreading vertical loads horizontally. This occurs through shear forces in the joints.
8.5
Structural Design Procedure
The load distribution and failure modes of flexible asphalt and interlocking concrete pavement are very similar: permanent deformation from repetitive loads. Since failure modes are similar, a simplified procedure of the method is adapted from Reference 4 and the American Association of State Highway and Transportation Officials (AASHTO) 1993 Guide for Design of Pavement Structures (5). The following structural design procedure is for roads and parking lots. Design for heavy duty pavements such as port and airport pavements is covered in ICPI manuals
entitled, Port and Industrial Pavement Design for Concrete Pavers, and Airfield Pavement Design with Concrete Pavers.
8.6
Design Considerations
The evaluation of four factors and their interactive effects will determine the final pavement thickness and material. These include environment, traffic, subgrade soil strength, and pavement materials. The design engineer selects values representing attributes of these factors. The values can be very approximate correlations and qualitative assumptions. Each factor, however, can be measured accurately with detailed engineering studies and extensive laboratory testing. As more detailed information is obtained about each factor, the reliability of the design will increase.
The effort and cost in obtaining information about each should be consistent with the importance of the pavement. A major thoroughfare should receive more analysis of the soil subgrade and traffic mix than a residential street. Furthermore, the degree of analysis and engineering should increase as the subgrade strength decreases and as the anticipated traffic level increases. In other words, pavements for high volume traffic over weak soils should have the highest degree of analysis of each factor as is practical. Environment — Moisture and temperature significantly affect pavement. As moisture in
the soil or base increases, the load bearing capacity of the soil or the strength of the base decreases. Moisture causes differential heaving and swelling of certain soils, as well. Temperature can affect the load bearing capacity of pavements, particularly asphalt stabilized layers. The combined effect of freezing temperatures and moisture can lead to the two detrimental effects. First, expansion of the water during freezing can cause the pavement to heave. Second, the strength of the pavement materials can be reduced by thawing. These detrimental effects can be reduced or eliminated one of three ways. Moisture can be kept from entering the pavement base and soil. Moisture can be removed before it has a chance to weaken the pavement. Pavement materials can be used to resist moisture and movement from swelling or frost. Limited construction budgets often do not allow complete protection against the effects of moisture and freeze thaw. Consequently, their effects should be mitigated to the highest extent allowed by the available budget and materials. In this design procedure, the effects of moisture and frost are part of characterizing of the strength of subgrade soil and pavement materials. Subjective descriptions of drainage quality and moisture conditions influence design strength values for subgrade soils and unbound granular materials. In addition, if freeze-thaw exists, then soil subgrade strength is reduced according to the degree of its frost susceptibility. Traffic — When pavement is trafficked, it receives wear or damage. The amount of
damage depends on the weight of the vehicles and the number of expected passes over a given period of time. The period of time, or design life, is usually 20 years. Predicted traffic over the life of the pavement is an estimate of various vehicle loads, axle and wheel configurations, and the number of loads. The actual amount of traffic loads can often exceed the predicted loads.
Therefore, engineering judgement is required in estimating expected sources of traffic and loads well into the future. Damage to pavement results from a multitude of axle loads from cars, vans, light trucks, buses and tractor-trailers. In order to more easily predict the damage, all of the various ax le loads are expressed as damage from an equivalent standard axle load. In other words, the combined damaging effects of various axle loads are equated to the damaging effect of 18-kip (80 kN) equivalent single axle load (EALs) repetitions. Damage factors for other axle loads are shown in Table 1. For example, the table shows that a single axle load of 38-kip (169 kN) would cause the same pavement damage as approximately 30 passes of an 18-kip (80 kN) single axle. For pavements carrying many different kinds of vehicles, greater study is needed to obtain the expected distribution of axle loads within the design period. If no detailed traffic information is available, Table 2 can be used for general guidance by listing typical EALs as a function of road class. In some situations, the designer cannot know the expected traffic in five, ten or fifteen years into the future. Therefore, the reliability (degree of conservatism) of the engineer‘s predictions can be modified as follows: Adjusted EALs = FR x EALs (estimated or from Table 2) where FR is the reliability factor. Recommended reliability factors by road class are also given in Table 2, along with the corresponding adjusted EALs for use in the design. In some residential development projects, interlocking concrete pavement streets are constructed first and then housing is built. Axle loads from construction-related truck traffic should be factored into the base thickness design. The loads can be substantial compared to the lighter loads from automobiles after construction is complete. Soil Subgrade Support — The strength of the soil subgrade has the greatest effect in
determining the total thickness of the interlocking concrete pavement. When feasible, resilient modulus or soaked California Bearing Ratio (CBR) laboratory tests should be conducted on the typical subgrade soil to evaluate its strength. These tests should be conducted at the most probable field conditions of density and moisture that will be anticipated during the design life of the pavement. CBR tests are described in ASTM D 1883 (6) or AASHTO T 193 (7).
In the absence of laboratory tests, typical resilient modulus (Mr) values have been assigned to each soil type defined in the United Soil Classification System (USCS), per ASTM D 2487 (6), or AASHTO soil classification systems (see Tables 3 and 4). Three modulus values are provided for each USCS or AASHTO soil type, depending on the anticipated environmental and drainage conditions at the site. Guidelines for selecting the appropriate Mr value are summarized in Table 5. Each soil type in Tables 3 and 4 has also been assigned a reduced Mr value (far right column) for use only when frost action is a design consideration. Compaction of the subgrade soil during construction should be at least 98% of AASHTO T-99 or ASTM D 698 for cohesive (clay) soils and at least 98% of AASHTO T-180 or ASTM D 1557 for cohesionless (sandy and gravelly) soils. The higher compaction standards described in T-180 or D 1557 are preferred. The effective depth of compaction for all cases should be at least the top 12 inches (300 mm). Soils having an Mr of 4,500 psi (31 MPa) or less (CBR 3% or less) should be evaluated for either replacement with a material with higher bearing strength, installation of an aggregate subbase capping layer, improvement by stabilization, or use of geotextiles. Pavement Materials — The type, strength and thickness of all available paving materials
should be established. Crushed aggregate bases, or stabilized bases used in highway construction are generally suitable for interlocking concrete pavement. Most states, provinces and municipalities have material and construction standards for these bases. If none are available, then the standards found in ASTM D 2940 (6) may be used. Minimum recommended strength requirements for unbound aggregate bases should be CBR = 80% and CBR = 30% for subbases. For unbound aggregate base material, the Plasticity Index should be no greater than 6; the Liquid Limit limited to 25; and compaction should be at least 98% of AASHTO T-180 density. For unbound granular subbase material, the material should have a Plasticity Index less than 10, a Liquid Limit less than 25, and compaction requirements should be at least 98% of AASHTO T180 density. In-place density should be checked in the field as this is critical to the performance of the pavement. If an asphalt treated base is used, the material should conform to dense graded, well compacted, asphalt concrete specifications, i.e., Marshall stability of at least 1800 pounds (8000 N). Cement treated base material should have a 7 day unconfined compressive strength of at least 650 psi (4.5 MPa).
Recommended minimum base thicknesses are 4 in. (100 mm) for all unbound aggregate layers, 3 in. (75 mm) for asphalt-treated bases, and 4 in. (100 mm) for cement-treated bases. A minimum thickness of aggregate base (CBR=80) should be 4 in. (100 mm) for traffic levels below 500,000 EALs and 6 in. (150 mm) for EALs over 500,000. Bedding sand should be consistent throughout the pavement and not exceed 1.5 in. (40 mm) after compaction. A thicker sand layer will not provide stability. Very thin sand layers (less than 3 /4 in. [20 mm] after compaction) may not produce the locking up action obtained by sand migration upward into the joints during the initial compaction in construction. The bedding layer should conform to the gradation in ASTM C 33 (6), as shown in Table 6 below. Do not use screenings or stone dust. The sand should be as hard as practically available.
Joint sand provides vertical interlock and shear transfer of loads. It can be slightly finer than the bedding sand. Gradation for this material can have a maximum 100% passing the No. 16 sieve (1.18 mm) and no more than 10% passing the No. 200 sieve (0.075 mm). Bedding sand may be used for joint sand. Additional effort in filling the joints during compaction may be required due to its coarser gradation. See ICPI Tech Spec 9, Guide Specification for the Construction of Interlocking Concrete Pavement for additional information on gradation of bedding and joint sand, as well as ICPI Zaphers guide specifications. Concrete pavers should conform to the ASTM C 936 (6) in the U.S. or CSA A231.2 (8) in Canada. A minimum paver thickness of 3.15 inches (80 mm) is recommended for all pavements subject to vehicular traffic, excluding residential driveways. As previously mentioned, the units should be placed in a herringbone pattern. No less than one-third of a cut paver should be used along the edges. Research in the United States and overseas has shown that the combined paver and sand layers stiffen as they are exposed to greater numbers of traffic loads. The progressive stiffening, or ―lock up,‖ generally occurs early in the life of the pavement, before 10,000 EALs. Once this number of loads has been applied, Mr = 450,000 psi (3100 MPa) for the 3.125 in. (80 mm) thick paver and 1 in. (25 mm) of bedding sand. Pavement stiffening and stabilizing can be accelerated by static proof-rolling with an 8 – 10 ton (8 – 10 T) rubber tired roller.
The above modulus is similar to that of an equivalent thickness of asphalt. The 3.125 in. (80 mm) thick pavers and 1 in. (25 mm) thick bedding sand have an AASHTO layer coefficient at least equal to the same thickness of asphalt, i.e., 0.44 per inch (25 mm). Unlike asphalt, the modulus of concrete pavers will not substantially decrease as temperature increases, nor will they become brittle in cold climates. They can withstand loads without distress and deterioration in temperature extremes.
COURSE OUTCOME 4 Able to judge and manually carry out design of infrastructure elements (earthworks, road, drainage, water reticulation, sewerage) by applying relevant codes.
Prepared by: Mohd Gazali Bin Alimuddin Checked by : Prof Madya Dr. Othman Jaafar
PROJECT: Construction of a school Part of Structure: Road Design Date: 18 May 2013 Step
Explanation/Calculations
References
Design Speed Road
Since the development area is within UKM, the road cl. 2.1.
Classification
is considered to be urban.
ATJ 8/86
Therefore, it is classified as Urban.
Finding Average
The value of ADT is estimated roughly based on the cl. 2.5
Daily Traffic
number of parking spaces available within the whole ATJ 8/86
(ADT)
site. According to the architectural drawings, there are less than 100 parking spaces available within all the buildings. Therefore, conservatively, the ADT is considered as 150.
Design Standard
Once the value for ADT is obtained, the design cl. 2.5, standard for the road can be deduced.
Table 2-3
Since the ADT is equal to 150, and the region is ATJ 8/86 rural, the design standard is U2.
Topography
The topography of the project site will affect the cl. 3.1 parameters considered in the road design. For this project, the maximum slope is 3.75%, resulting into the terrain to be Rolling.
ATJ 8/86
Prepared by: Mohd Gazali Bin Alimuddin Checked by : Prof Madya Dr. Othman Jaafar
PROJECT: Construction of a school Part of Structure: Road Design Date: 18 May 2013 Step
Explanation/Calculations
References
Design Speed
The value for design speed is an important parameter Table 3in further calculations for the road design. It depends 2A, on the type of terrain and the road classification. The ATJ 8/86. design speed for the road is chosen as 50 km/hr.
Capacity Design ADT
Estimated (as above mentioned) to 150.
cl. 3.3.1, ATJ 5/85.
Percentage of
Since the development area is a residential and
commercial
institutional one, there is less probability of having cl. 3.3.2
vehicles, Pc
commercial or heavy vehicles on the roads regularly, ATJ 5/85. except for buses. Therefore, Pc is assumed to be 10%.
Rate of growth, r
Assumed to be 5%.
cl. 3.3.3 ATJ 5/85.
Initial average commercial
Vo = ADT x 365 x 0.5 x Pc/100 = 2 738 pcu
cl. 3.3.4 ATJ 5/85.
traffic for one direction, Vo The conservative years of projected traffic is taken as Years of projected 20 years. However, to be economical, a usual value cl. 3.2.2 traffic
of 10 years is considered in design.
ATJ 5/85.
Prepared by: Mohd Gazali Bin Alimuddin Checked by : Prof Madya Dr. Othman Jaafar
PROJECT: Construction of a school Part of Structure: Road Design Date: 18 May 2013 Step
Total no. of
Explanation/Calculations
( )
vehicles for one direction, Vc
Total daily traffic at end of design years, Vx
cl. 3.3.5
commercial
References
ATJ 5/85.
( )
34 432 pcu
( ) where V1 is the average daily traffic per lane
cl. 3.3.7 ATJ 5/85.
V1 = ADT/2 V1 = 150/2 = 75
( ) Vx = 122 vehicles per day per lane
Equivalence
The equivalence factor depends on the percentage of Table 3.1
Factor, e
heavy vehicles, Pc. Therefore, value of e is 1.2
ATJ 5/85.
Total equivalent
The value of ESA is the product of e and Vc.
cl. 3.3.9
Standard Axles,
ATJ 5/85.
ESA
413 18.4
Prepared by: Mohd Gazali Bin Alimuddin Checked by : Prof Madya Dr. Othman Jaafar
PROJECT: Construction of a school Part of Structure: Road Design Date: 18 May 2013 Step
Explanation/Calculations
References
Max hourly traffic The maximum hourly traffic volume is given by:
cl. 3.3.12
volume, c
ATJ 5/85.
where I – ideal one-way hourly capacity R - Roadway Factor T - Traffic Reduction Factor I = 2000 (for one lane)
Table 3.2
R = 1.00 (road width = 7.3m and shoulder width =
Table 3.3
1.5m)
Table 3.4
ATJ 5/85.
()
1.00 Therefore,
vehicles per hour per lane
One-way daily
It is assumed that the maximum hourly traffic
cl. 3.3.13
capacity, C
represents 10% of the daily traffic. Thus,
ATJ 5/85.
vehicles per day per lane
Prepared by: Mohd Gazali Bin Alimuddin Checked by : Prof Madya Dr. Othman Jaafar
PROJECT: Construction of a school Part of Structure: Road Design Date: 18 May 2013 Step
Explanation/Calculations
Level of Service
Level of Service (LOS) is the ratio of volume of the
References
road to the capacity of the road. As obtained from the above calculations: V = 124 vehicles per day per lane C = 1400 vehicles per day per lane
= 0.09
Since LOS = 0.09c, which lies between 0.00 and Table 3-4 0.59, the Level of Service is A. LOS A refers free ATJ 8/86 flow with low volumes, densities and high speeds. Thus, the design is adequate.
Pavement Design
Pavement Layout
Wearing Course - Asphalt Binder Course - Asphalt Base Course – Mechanically Stabilised Crushed Aggregates Sub Base Course - Sand
Prepared by: Mohd Gazali Bin Alimuddin Checked by : Prof Madya Dr. Othman Jaafar
PROJECT: Construction of a school Part of Structure: Road Design Date: 18 May 2013 Step
Explanation/Calculations
Required
Class of road: U2
parameters
ADT : 150
previously
ESA: 41318.4 = 4.13 x 10
References
4
obtained
CBR
CBR refers to the strength of the subsoil. It is cl. 3.5.1 assumed to be 5%.
equivalent
ATJ 5/85.
Equivalent
The
thickness
is
the
thickness Figure 2
Thickness, TA and
theoretically required while the corrected equivalent ATJ 5/85.
Corrected
thickness is a measure of minimum thickness
Equivalent
required for the road pavement. Their values are
Thickness, TA`
dependent on both ESA and CBR values. From Thickness Design Nomograph, the values of TA and of TA` are 11.0cm and 10.0 cm, respectively.
Thickness of
Determining the thickness of pavement is a trial and cl. 3.5.2
Pavement, TA
error process. The depth of each layer of the ATJ 5/85. pavement is to be assumed and calculation carried out in order to get an adequate design. TA = a1D1 + a2D2 +a3D3 +a4D4
Prepared by: Mohd Gazali Bin Alimuddin Checked by : Prof Madya Dr. Othman Jaafar
PROJECT: Construction of a school Part of Structure: Road Design Date: 18 May 2013 Step
Explanation/Calculations
Thickness of
Values of a1, a 2, a 3 and a4 are obtained from the JKR
Pavement, TA
standard. a1: 1.00 ; a2: 1.00; a3: 0.32 and a4: 0.23
References
Table 3.5 ATJ 5/85.
Note: 1. The values for the above coefficients are dependent on the materials used for each layer. It is common in Malaysia to use the following: Wearing Course: Asphalt
Table 3.5
Binder Course:
ATJ 5/85.
Base Course:
Asphalt Mechanically Stabilised Crushed Aggregates
Sub Base Course: Sand 2. The depths chosen for each layer in the pavement Table 3.6 should follow the minimum thicknesses in the JKR ATJ 5/85. standard.
Therefore, Trial 1: D1: 4cm; D2: 5cm; D3: 5cm and D4: 10cm TA = (1.00 x 4) + (1.00 x 5) + (0.32 x 5) + (0.23 x 10) = 12.9 cm
Prepared by: Mohd Gazali Bin Alimuddin Checked by : Prof Madya Dr. Othman Jaafar
PROJECT: Construction of a school Part of Structure: Road Design Date: 18 May 2013 Step
Explanation/Calculations
The value of TA is less than that of T A`, thus, each layer of pavement has a thickness as chosen as above.
Thus, Wearing Course: 4cm Binder Course: 5 cm Base Course: 5cm Sub Base Course: 10 cm
References
Prepared by: Mohd Gazali Bin Alimuddin Checked by : Prof Madya Dr. Othman Jaafar
PROJECT: Construction of a school Part of Structure: Road Design Date: 18 May 2013 Step
Explanation/Calculations
Design Speed
The geometric design depends on the design speed. It
References
was previously obtained in the traffic design. Design Speed = 50 km/hr
Road cross-
Lane width = 7.30m
Table 5-3
section
Marginal Strip width = 0.00m
Table 5-3
geometries
Shoulder Width = 1.50m
Table 5-4A
Alignment
Maximum Superelevation = 0.10
Pg 6
Parameters
Horizontal Alignment:
General
Minimum radius = 85m
Summary-
Stopping Sight Distance = 65m
Geometric
Passing Sight Distance = 350m
DesignCriteria for
Vertical Alignment:
Roads in
Maximum Desirable Grade = 7%
Rural
Maximum Grade = 10%
Areas.
Crest Vertical Curve = 10 Sag Vertical Curve = 12
COURSE OUTCOME 5 Able to design infrastructure elements and generate drawings using relevant computer software (Excel spread sheet, AutoCad and other design software). *(Refer to Drawing Plan)
COURSE OUTCOME 7 “Able to verbally present infra and sub-structures design project in presentation session.”
COURSE OUTCOME 11 “Able to execute life-long learning activities in project activities.”
Life Long Learning Through This Project
In this project I already learnt many things that were involved in construction process mostly in road construction. I had learnt what sho uld be consider before we starting the roadwork such as do the site assessment first, see what types of soils on the proposed area and see the type of vegetation there so we can easily know what to do next. Such an example i can say, when we already know the type of soil there in proposed site, whether it is too swampy or dry land, we can know what method and what lab test we should do to accomplished the work. Every single work to be accomplished has its own method to solve the problem. Instead of doing some site assessment, i also learnt to investigate the surrounding of the proposed site. In doing this, i do go sightseeing to observe what trend in the nearest area such as the traffic flow, available facilities, and the residents. It is important because it might give an impact to the time of completion and cost of the project in terms of transporting material, fuel, and traffic. If the engineer or the construction player did not concern of this, the project will be failed in any time, may not last long and will cost them more. Moreover, in this project also had teaches me how to cooperate with different person with different role. Every task related to each other. As for me, i do the roadwork and some parking and i should cooperate with my members who done the sewerage, drainage and the earthwork task. Without them, my work will stuck and in the other word my work will be delay. I need to know the proposed platform level from earthwork process to make it as my current level to do my own proposed platform level. I also need to cooperate with the the one who handle the sewerage and drainage task. This is important so i can propose the geometric pavement design, the layout of roadwork and the place I can proposed the parking. If i skip this thing, it will make it hard for them to placing the sewerage pipe and drainage pipe. Other than that, I already learnt many type of innovation in roadwork available in the current industries and mostly a more sustainable product in terms of material used and also sustainable plan practices in road construction. Such an example sustainable plan from ‗Greenroads‘. This system outlines minimum requirements to qualify as a green roadway, including a noise mitigation plan, storm-water management plan and waste management plan.
In this project also we already learn how to handle some software such as Autocad, Esteem, Geostudio and others in analysis, sketching, and drawing. But the main problem is we lacked of exposure from the professionals. We need to learn it by ourself and that will take too much time to complete one analysis. I hope in the future, there will be more exposure to the student on how to handle certain software to be use. One more thing, the problem that I faced when doing the drawing plan. I do not know what specification i should follow to get a better drawing plan just like the real drawing plan that were used for engineer in planning a project. I hope there will be some example of it. Lastly i hope, the learning scheme of this subject should be prepared wisely so that the student could learn something without worrying about the date to submit this projecy and just copying this or that from book and internet.
COURSE OUTCOME 12 “Able to develop or propose or incorporate or plan new structures from existing knowledge on the impact of professional Civil and Structural Engineering solutions in societal and environmental contexts and the need for sustainable development in the design project.”
The Role of the Civil Engineer in Sustainable Development
sustainability as a set of economic, environmental and social conditions in which all of society has the capacity and opportunity to maintain and improve its quality of life indefinitely, without degrading the quantity, quality or the availability of natural resources and ecosystems. Moreover, sustainable development is the process of converting natural resources into products and services that are more profitable, productive, and useful, while maintaining or enhancing the quantity, quality, availability and productivity of the remaining natural resource base and the ecological systems on which they depend. As we all know, Civil Engineering is one of the, if not the most important keystones of civilization, or development as we recognize it today. Historically too, the ruins or remains of great structures and infrastructure like the Dagobas and irrigation systems of Anuradhapura, Pyramids of Egypt, Stonehenge of England, buildings and fortresses of the ancient Roman, Greek and Maya cultures are the evidence that we have to learn about the height and the sophistication of civilization of those communities. Civil Engineering involves providing irrigation for cultivation, construction of housing and offices, schools, hospitals, hotels and all sorts of buildings to provide living, learning and working spaces, roads and railways, both above and below ground, bridges to connect inaccessible points, harbours and airports for air travel and shipping and infrastructure like water supply and wastewater collection and disposal systems, storm drainage and flood protection schemes, coast protection structures and so on. Not only that, Civil Engineers are called upon to put up telecommunication towers for the telecom engineers to fix their equipment, pylons for the electrical engineers to support the power lines, and to design and install optical fibre cabling for the computer engineers. We plan, design and construct all these facilities, and we have always been trained to do that with great attention to safety, comfort, serviceability and economy. A civil engineer would never design a building without checking the safety of the critical components against structural failure due dead loads, live loads, wind loads etc., according to the Codes of Practice, a dam without checking for overtopping, toppling or sliding, a drainage system without providing capacity for a predetermined rainfall intensity and return period, a highway or railway without
providing the necessary curvatures to ensure safety and comfort and so on. Nor would a Civil Engineer plan or design a structure or facility that would seem insecure or is insufficient for the purpose for which it is meant. He or she would select all materials very carefully to ensure its strength, serviceability and economy. We have heard of the famous saying ‘an engineer is a person who can do for one ringgit, what any fool can do for two‘, and often we find engineers who economize even at the expense of aesthetics! Our thinking has been trained in this fashion, and it only feels right when we do our work according to these concepts. While doing all this to provide a better quality of life for the population, we make use of, and sometimes render unusable, large amounts of natural resources, sometime even without realizing it. When we construct a building, for example, we use sand, minerals that go into cement, metal (stones), iron and aluminium, timber etc. as construction materials, fresh water, and fuel for transport of materials and people and for operation of equipment, which are all natural resources. But sometimes we tend to forget that we are making use of a very limited resource, land, to put up the building. It is the same with roads, railways, airports, carparks or any other land based construction. We deprive the land of being used for other productive uses, and reduce the vegetation cover, which cleans up the air, by absorbing the green house gases that cause global warming. Most of us do not think twice about removing the vegetation and topsoil from a construction site, or cutting down a tree that is obstructing a predetermined road or railway alignment or a power line. When we want to provide irrigation for agriculture, we have no qualms about putting up a dam across a stream and making a reservoir, drowning all plants and small animals and insects, particularly if no people are adversely affected. No wonder we give the impression to the public, particularly the so called environmentalists that we do not care for the environment as much as we should. We used to assume that such destruction of the environment is the price people have to pay to get what they want – a trade-off situation that is inevitable. However, now there is another dimension or a concept that has become very important as the world has realized the diminishing nature of th e natural resources that are available to us. The earth can be compared to a spaceship travelling at very high speed through the Universe, with all the materials needed for our survival are packed into it. The only external
resource is the sun‘s energy, which is available to us as a perpetual resource. It is not like travelling in a train or bus, where we could stop at a station or bus stop and have a cup of tea and a bun. The earth has a life support system, which is governed by the natural recycling of matter and the one way flow of energy from the sun which can be converted to other forms, but loses a part of it as low quality heat every time it is converted. We learn about these as the law of conservation of mass and the two laws of Thermodynamics. Some resources like trees and animals get replenished fast when used, and we call them ‗renewable resources‘. Some resources take a very long time to be replenished, like coal and fossil fuel – these are called ‗non-renewable resources‘. Then there are resources that are not affected by how much is used, like the sun light, flowing water, wind and tide. These are called perpetual resources. Energy produced from non-renewable resources like coal or petroleum is called ‗nonrenewable energy‘, while energy produced from renewable resources like wood (dendro power), waste digestion (biogas) and vegetable oils (Bio diesel), or perpetual resources like flowing water (hydropower), sunlight (solar power), wind and tide is called ‗renewable‘ energy. One thing we must remember is that even though renewable resources can get replenished fast, they can only last if we use them at a rate slower than they get replenished. If we use them indiscriminately, without concern for their re-growth, they will be the ones to disappear even before the non-renewable resources. With the growing world population and the sophistication of our lifestyles, the limited resources on earth are getting depleted at a rate higher than the rate at which it is replenished naturally. We use them too much, and also make them unusable by polluting them. Added to this are the effects of climate change and global warming, experience by the world due to the increased emissions of green house gases carbon dioxide, methane and oxides of nitrogen by human activities such as burning fossil fuels and discharge of untreated wastes into the environment. This is why we have to make a conscious effort to limit our resource use and stop polluting the environment, allowing the earth to continue supporting life on earth by its own natural processes. For sustainable development to be achieved, professional practice in engineering needs to have a wider scope than the development of elegant solutions to narrowly specified technical
problems. The challenge faced by Civil engineers in sustainable development is to make their contribution to society to:
Reduce the adverse environmental and social aspects of developments
Improve their environmental performance
Improve their contribution to a high quality of life
Help society to move towards a more sustainable lifestyle, and
Ensure that products, services and infrastructure meeting these criteria are competitive in the market place, and ideally the most competitive The civil engineering profession recognizes the reality of limited natural resources, the
desire for a sustainable practices (including life-cycle analysis and sustainable design techniques), and the need for social equity in the consumption of resources. To achieve these objectives such implementation strategies should be made:
Promote broad understanding of economic, environmental, political, social, and technical issues and processes as related to sustainable development;
Advance the skills, knowledge and information necessary for a sustainable future; including habitats, natural systems, system flows, and the effects of all phases of the life cycle of projects on the ecosystem;
