project report 1

INDUSTRIAL TRAINING AT KIRATPUR NERCHOWK EXPRESSWAY NH-21

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CONTENTS:

1. Synopsis

2. Company Profile

3. About the Project

4. Introduction

4.1 Importance of transportation………………………………………………

4.2 Different modes of transportation…………………………………………

4.3 History of roads…………………………………………..

4.4 History of Road development in India……………………………………………….

4.5 Importance of Road Transportation in India……

4.6 Advantages of Roads………

5. Highway Development and Planning

6. Types of pavement

7. Designing of flexible pavement

8. Equipments Used

9. Testing

10. Conclusion

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ACKNOWLEDGEMENTS

First and foremost we would like to thank God for providing the immense opportunity to

have Industrial Training at GHV Pvt. Lmt.

We want to express our gratitude to Er. Suman Kumar (D.P.M. Planning & Billing), Er

MI Haq(D.P.M. Structure), Er. Gaurav Sharma (Site Engineer) , Er. Davendra Sahni, Er.

Pankaj Kumar, Er. Arun Kumar, Er. Gaurav Sharma, Er. SH Pande and Er. Tarun Kumar.

Our acknowledgements would be incomplete if we wouldn’t thank our HOD Dr. SP

Guleria for encouraging us. The concept told by our Highway lecturer Er. Sanjay Kumar

has eased us to grasp the practical work going at the site. So, we want to thank them too.

Last but not the least we want to thank each other for being such a wonderful team

members.

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1. SYNOPSIS:

In the following report we have explicated about Kiratpur-Nerchowk Express way NH-

21, needs of transport, techniques followed by developers of the projects, testing of

materials, construction of Four lane, construction pattern followed, instruments and

machinery used.

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2. COMPANY PROFILE:

COMPANY NAME: GHV(India) Private Limited.

ADDRESS:

PERMANENT ADDRESS: AML Centre-1,8 Mahal Industries Area,

Mahakali Caves Road, Andheri (East), Mumbai-400093.

Tel: 022-67250014/15, Fax: 022-67250016, Email: [email protected]

Web: www.ghvgroup.com

SECTION UNDER CONSTRUCTION: Dehar to Nerchowk (from km 154 to km

188.837)

SHARE IN GROSS BUGDET: 225.58crore

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mailto:[email protected]


3. ABOUT THE PROJECT

The Cabinet Committee on Infrastructure approved the implementation of the project of four laning of Kiratpur – NerChowk section on NH 21 in Himachal Pradesh under NHDP Phase III on DBFOT basis in BOT (Toll) mode of delivery. The total project cost estimated will be Rs.2356.20 crore out of which Rs.537.37 crore will be for the land acquisition, rehabilitation, resettlement and pre-construction. The total length of the project will be 84.380 Km. The project, on completion, will reduce the time and cost of travel for traffic, particularly heavy traffic, plying between Kiratpur and Ner Chowk. It will also increase the employment potential for the local labourers for the project activities. The main objective of the project is to expedite the improvement of infrastructure in Himachal Pradesh and also in reducing the time and cost of travel for traffic, particularly heavy traffic, plying between Kiratpur and Ner Chowk. The National Highway No. 21 is an important link connecting national capital and tourist destination of Manali in Himachal Pradesh. Also the NH 21 is the major link to leh in ladak.

The project is covered in the districts of Rupnagar, Bilaspur and Mandi in Himachal Pradesh

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Project details:-

Name of project Kiratpur –Nerchowk expressway NH 21

Date of signing concession agreement March 16,2012

Date of final closure September 2,2012

Concession end period 2041

Concession period* 28yrs

Construction period 1095days(from Appointed date)

Extension 2yrs

Tender Type DBFOT*

EPC* contractor ITNL

Sub contractor IL&FS

GHV PVT Ltd.

VIL

Supervision Consultant IL&FS

Total length (flexible pavement) 84.375km (from km 104.298 to km

188.837)

Road work 67.3km

No. of minor bridges 29

No. of major bridges 18

No. of main tunnels 05

No. of toll plaza 02

Estimated project cost 2356.20crore

Total cost for land acquisition 537.37crore

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Total cost for road construction 1436.08crore

Total cost for other structures 382.75crore

Share of IL&FS 1210.50crore

Share for GHV Pvt Ltd. 225.58crore

Share for VIL Pvt 382.75crore

*DBFOT-Design-Build-Finance-Operate-Transfer

These projects involve designing and building the infrastructure, operating them for a specific period and transferring the ownership of the project to the government after specific timeframe which runs normally between 10 and 30 years.

*EPC- Engineering Procurement and Construction

Under an EPC contract, the contractor designs the installation, procures the necessary materials and builds the project, either directly or by of the work. In some cases, the contractor carries the project risk for schedule as well as budget in return for a fixed prise, depending on the agreed scope of work.

This is often done in situations where the construction risk is too great for the contractor or when the owner does the construction. The ‘keys’ to a commissioned plant are handed to the owner for an agreed amount, just as a builder hands the keys of a flat to the purchaser. It requires good understanding by the EPCC to return a profit. An owner decides for an EPC contract for reasons that include:

1. Reduced stress for owner

2. Easy work and growth of the company.

3. Single point of contact for owner simplifies communications.

4. Ready availability of post-commissioning services

5. Ensures quality and reduces practical issues faced in other ways

6. Owner protected against changing prices for materials, labor, etc.

7. Cost is known at the start of the project.

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4. Introduction

4.1 Importance of transportation

Development is related at improving the welfare of a society through appropriate social, political and economic conditions. The expected outcomes are quantitative and qualitative improvements in human capital (e.g. income and education levels) as well as physical capital such infrastructures (utilities, transport, telecommunications). While in the previous decades, development policies and strategies tended to focus on physical capital, recent years has seen a better balance by including human capital issues. Irrespective of the relative importance of physical versus human capital, development cannot occur without both as infrastructures cannot remain effective without proper operations and maintenance while economic activities cannot take place without an infrastructure base. Because of its intensive use of infrastructures, the transport sector is an important component of the economy and a common tool used for development. This is even more so in a global economy where economic opportunities are increasingly related to the mobility of people, goods and information. A relation between the quantity and quality of transport infrastructure and the level of economic development is apparent. High density transport infrastructure and highly connected networks are commonly associated with high levels of development. When transport systems are efficient, they provide economic and social opportunities and benefits that result in positive multipliers effects such as better accessibility to markets, employment and additional investments. When transport systems are deficient in terms of capacity or reliability, they can have an economic cost such as reduced or missed opportunities and lower quality of life.

At the aggregate level, efficient transportation reduces costs in many economic sectors, while inefficient transportation increases these costs. In addition, the impacts of transportation are not always intended and can have unforeseen or unintended consequences. For instance congestion is often an unintended consequence in the provision of free or low cost transport infrastructure to the users. Transport also carries an important social and environmental load, which cannot be neglected. Assessing the economic importance of transportation requires a categorization of the types of impacts it conveys. These involve core (the physical characteristics of transportation), operational and geographical dimensions.

4.2 Different modes of Transportation

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Transportation developments that have taken place since the beginning of the industrial revolution have been linked to growing economic opportunities. At each stage of human societal development, a particular transport technology has been developed or adapted with an array of impacts. Five major ways of economic development where a specific transport technology created new economic, market and social opportunities can be suggested:

Seaports. Linked with the early stages of European expansion from the 16th to the 18th centuries, commonly known as the age of exploration. They supported the early development of international trade through colonial empires, but were constrained by limited inland access.

Rivers and canals. The first stage of the industrial revolution in the late 18th and early 19th centuries was linked with the development of canal systems in Western Europe and North America, mainly to transport heavy goods. This permitted the development of rudimentary and constrained inland distribution systems.

Railways. The second stage of industrial revolution in the 19th century was linked with the development and implementation of rail systems enabling more flexible and high capacity inland transportation systems. This opened up substantial economic and social opportunities through the extraction of resources, the settlement of regions and the growing mobility of freight and passengers.

Roads. The 20th century saw the rapid development of comprehensive road transportation systems, such as national highway systems, and of automobile manufacturing as a major economic sector. Individual transportation became widely available to mid income social classes, particularly after the Second World War. This was associated with significant economic opportunities to service industrial and commercial markets with reliable door-to-door deliveries. The automobile also permitted new forms of social opportunities, particularly with suburbanization.

Airways and information technologies. The second half of the 20th century saw the development of global air and telecommunication networks in conjunction with economic globalization. New organizational and managerial forms became possible, especially in the rapidly developing realm of logistics and supply chain management. Although maritime transportation is the physical lynchpin of globalization, air transportation and IT support the accelerated mobility of passengers, specialized cargoes and their associated information flows.

4.3 History of Roads

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The beginning of roads starts as long ago as the Stone Age when trackways were made by

primitive man to help him trade with other primitive people. However, it was the Romans

who first built roads as we know them today. These roads were one of the greatest

achievements of the Roman Empire. The first Roman road was the Via Appia and it was built

in the year 312 B.C. This road stretched for over 6,018 kilometres across Western and

Southern Europe. Roman roads were built mainly for the armies to conquer other countries,

letting them travel quickly and safely, but, they were soon used for trade and for people to

simply go from one city to another.

Roman roads were built in a straight line as they did not have to worry about who owned the

land or the effect of the roads on the environment.They would also have been able to seen

enemies approaching. These roads show how skilful the Romans were as engineers and

planners as their techniques meant that the roads lasted for centuries. By the 18 th century

most of the traffic was horse carts and new wheeled vehicles.

The soft dirt track roads were never built to carry those sort of vehicles and were not able to

cope with this heavy traffic. So came the era of the Turnpike trusts - an imaginative new way

of getting the roads built and maintained. Turnpike trusts were made up of a group of people

who would get together and ask for permission from Parliament to take over a section of road,

or build a new one, for about 21 years. They would pay for its maintenance by collecting tolls

from the people who used them. These roads were commonly called turnpike roads. You can

still see some signs of the location of these roads where you see tiny houses on the edge of the

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road. Where the man who collected the tolls lived. Many roads were improved this way and

the Turnpike trusts experimented with new ways to build roads, adding new methods of

making roads stronger and last longer so that wheeled traffic could travel more easily.

New Road construction techniques were developed by John MacAdam, Thomas Telford and

John Metcalfe. Each of them put forward the idea of building raised, cambered roads which

allowed water to drain off them as fast as possible. MacAdam's technique, which used tar

mixed with roadstone and called tarmacadam, became widely used and, eventually developed

into the modern method of road building.

Metcalf Construction

By the late 18th and early 19th centuries, new methods of highway construction had been

pioneered by the work of two British engineers, Thomas Telford and John Loudon McAdam,

and by the French road engineer Pierre-Marie-Jérôme Trésaguet.

The first professional road builder to emerge during the Industrial Revolution was John Metcalf,

who constructed about 180 miles (290 km) ofturnpike road, mainly in the north of England, from

1765, when Parliament passed an act authorising the creation of turnpike trusts to build

new toll funded roads.He believed a good road should have good foundations, be well drained

and have a smooth convex surface to allow rainwater to drain quickly into ditches at the side. He

understood the importance of good drainage, knowing it was rain that caused most problems on

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the roads. He worked out a way to build a road across a bog using a series of rafts made from

ling (a type of heather) and furze (gorse) tied in bundles as foundations. This established his

reputation as a road builder since other engineers had believed it could not be done. He acquired

a mastery of his trade with his own method of calculating costs and materials, which he could

never successfully explain to others.

Trésaguet Construction

Pierre-Marie-Jérôme Trésaguet is widely credited with establishing the first scientific

approach to road building in France at the same time. He wrote a memorandum on his method

in 1775, which became general practice in France. It involved a layer of large rocks, covered

by a layer of smaller gravel. The lower layer improved on Roman practice in that it was based

on the understanding that the purpose of this layer (the sub-base or base course) is to transfer

the weight of the road and its traffic to the ground, while protecting the ground from

deformation by spreading the weight evenly. Therefore, the sub-base did not have to be a self-

supporting structure. The upper running surface provided a smooth surface for vehicles, while

protecting the large stones of the sub-base.

Trésaguet understood the importance of drainage by providing deep side ditches, but he

insisted on building his roads in trenches, so that they could be accessed from the sides, which

undermined this principle. Well-maintained surfaces and drains protect the integrity of the sub-

base and Trésaguet introduced a system of continuous maintenance, where a roadman was

allocated a section of road to be kept up to a standard.

Telford Construction

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The surveyor and engineer Thomas Telford also made substantial advances in the engineering

of new roads and the construction of bridges. His method of road building involved the digging

of a large trench in which a foundation of heavy rock was set. He also designed his roads so

that they sloped downwards from the centre, allowing drainage to take place, a major

improvement on the work of Trésaguet. The surface of his roads consisted of broken stone. He

also improved on methods for the building of roads by improving the selection of stone based

on thickness, taking into account traffic, alignment and slopes. During his later years, Telford

was responsible for rebuilding sections of the London to Holyhead road.

Macadam Construction

It was another Scottish engineer, John Loudon McAdam, who designed the first modern roads.

He developed an inexpensive paving material of soil and stone aggregate (known

as macadam). His road building method was simpler than Telford's, yet more effective at

protecting roadways: he discovered that massive foundations of rock upon rock were

unnecessary, and asserted that native soil alone would support the road and traffic upon it, as

long as it was covered by a road crust that would protect the soil underneath from water and

wear. Also unlike Telford and other road builders, McAdam laid his roads as level as possible.

His 30-foot-wide (9.1 m) road required only a rise of three inches from the edges to the center.

Cambering and elevation of the road above the water table enabled rain water to run off into

ditches on either side.

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Size of stones was central to McAdam's road building theory. The lower 200-millimetre

(7.9 in) road thickness was restricted to stones no larger than 75 millimetres (3.0 in). The upper

50-millimetre (2.0 in) layer of stones was limited to 20 millimetres (0.79 in) size and stones

were checked by supervisors who carried scales. He also wrote that the quality of the road

would depend on how carefully the stones were spread on the surface over a sizeable space,

one shovelful at a time.

McAdam directed that no substance that would absorb water and affect the road by frost should

be incorporated into the road. Neither was anything to be laid on the clean stone to bind the

road. The action of the road traffic would cause the broken stone to combine with its own

angles, merging into a level, solid surface that would withstand weather or traffic

Through his road-building experience McAdam had learned that a layer of broken angular

stones would act as a solid mass and would not require the large stone layer previously used to

build roads. By keeping the surface stones smaller than the tyre width, a good running surface

could be created for traffic. The small surface stones also provided low stress on the road, so

long as it could be kept reasonably dry. In practice, his roads proved to be twice as strong as

Telford's roads.

Although McAdam had been adamantly opposed to the filling of the voids between his small

cut stones with smaller material, in practice road builders began to introduce filler materials

such as smaller stones, sand and clay, and it was observed that these roads were stronger as a

result. Macadam roads were being built widely in the United States and Australia in the 1820s

and in Europe in the 1830s and 1840s.

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4.4. HISTORY OF ROAD DEVELOPMENT IN INDIA

It is believed that the oldest mode of travel was on the footpaths later on, with the development of bullock carts and other simple animal drawn vehicles, roads were also developed. These early roads were constructed as kutcha roads, consisting of ordinary earth. The kutcha roads were soon deteriorated under heavy bullock cart traffic Thus metalled roads came into existence. The first indication of these roads in pre-historic period has been revealed by the excavations at Mohenjodaro and harappa (paklistan). It is believed that these towns were constructed 3500 years B.C. Earth and paved street pavements have been found.With the development of techniques of modern road construction in England and many other countries, extensive development in metaled roads took place during British period in India. These roads were constructed on the basis of techniques suggested by Telford and Macadam in England.Water bound macadam (WBM) construction, based on Macadam technique, was commonly adopted. This method is now considered as one of the popular methods of construction road pavements. In this method, the brokenstones ofthe base and of wearing course, if any, are boundtogether by the stonedust in the poresence of moisture, WBM construction techniqueis still in use in our country both as a finished road pavements and also as good base coat for superior road pavement. With the developments of fast moving and pklneumatic tyred vehicles WBM road pavements could not lost longer as they create dust nuisance during dry weather and became muddy during monsoon. In order to minimize dust nuisance, a thin coat of bituminous materials was tried with varying degrees of success.

Later on, it was experienced that thin surface coating of bituminous materials was not sufficient to take the load of heavy commercial vehicles. So development of bituminous macadam pavements took place for better results, superior materials like bituminous concrete pavements were also developed.The present trend of providing road pavements is to use cement concrete, plain as well as reinforced, for their construction. The cement concrete road pavements provide a good and an even riding surface They can be designed to take up the heaviest loads expected on the roads even in adverse soil and climatic conditions. Since concrete roads pavements involve heavy initial cost, therefore, they are not being extensively used in our country.

4.5. Importance of Road Transportation in India

1) Motor transports as well as road constructions have contributed significantly to the growth of the Gross National Product (GNP) all over the world, but India has remained significantly backward in this regard. Besides there is tremendous scope for creating employment through road construction and maintenance. Further, India needs increased road mileage, especially to open up the vast areas which cannot be reached except through roads.

2) Road transport is quicker, more convenient and more flexible. It is particularly good for short distance travel for movement of goods. Motor vehicles can easily collect passengers and goods

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from anywhere and take them to wherever they want to be dropped. Door-to-door collection and delivery are possible in the case of road transport. But in the case of railways, the lines are fixed and the railways do not have the flexibility of the roadways. Passengers and goods will have to be taken to the railway stations.

3) Roads are a necessary complement to railways. India is a country of villages and it is only roads which can connect villages and railways can connect towns. The railway stations will have to be properly served by a network of feeder roads. Only through these roads the railways can receive their passengers and goods. If railways are essential for the movement of goods and people for long distances, road transport is essential for such movement for short distances. Roads and railways are, therefore, not competitive but complementary.

4) Road transport is of particular advantage to the farmers. Good roads help the farmers to move their products, particularly the perishable products; like vegetables, quickly to the mandis and towns. Only by developing the road system, the farmer can be assured of a steady market for his products. It is the road system which brings the villagers into contact with the towns and the new ideas and the new systems from the towns.

5) Roads are highly significant for the defence of the country. For the movement of troops, tanks, armoured cars, and field guns etc. roads are essential. The great importance given to the construction of border roads to facilitate the movement of troops for the protection of the northern borders against the Chinese aggression is an example of the great importance of roads in the defence of the country.

4.6. Advantages of Roads

1. Roads play a very important role in the transportation of goods and passengers for short and medium distances.

2. It is comparatively easy and cheap to construct and maintain roads.

3. Road transport system establishes easy contact between farms, fields, factories and markets

and provides door to door service.

4. Roads can negotiate high gradients and sharp turns which railways cannot do. As such, roads

can be constructed in hilly areas also.

5. Roads act as great feaders to railways. Without good and sufficient roads, railways cannot

collect sufficient produce to make their operation possible.

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6. Road transport is more flexible than the railway transport. Buses and trucks may be stopped

anywhere and at any time on the road for loading and unloading passengers and goods whereas

trains stop only at particular stations.

7. Perishable commodities like vegetables, fruits and milk are transported more easily and

quickly by roads than by railways.

5. Highway Development and Planning

5.1 Necessity of planning

In the present era planning is considered as a pre-requisite before attempting any development

programme. This is particularly true for any engineering work, as planning is the basic need for

any new project or an expansion programme. Thus highway planning is the basic need for

highway development. Particularly planning is of great importance when the funds available are

limited whereas the total requirement is much higher. This is actually the problem in all

developing countries like India as the best utilization of available funds has to be made in a

systematic and planned way. The objectives of highway planning are briefly given below:

i. To plan a road net work for efficient and safe traffic operation, but at minimum cost.

Here the costs of construction, maintenance and renewal of pavement layers and the

vehicle operation costs are to be given due consideration.

ii. To arrive at the road system and the lengths of different categories of roads this could

provide maximum utility and could be constructed within the available resources during

the plan period under consideration.

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iii. To fix up date wise priorities for development of each road link based on utility as the

main criterion for phasing the road development programme.

iv. To plan for future requirements and improvements of roads in view of anticipated

developments.

v. To work out financing system.

The planning of road projects is a process becom- ing more detailed stage by stage. At

each stage, the level of planning accuracy and decision- making is adapted in accordance

with land use planning. the planning process has four stages: feasibility study,

preliminary engineering planning, final engineering planning and construction planning.

In minor road projects with limited impacts, planning and decision-making stages can be

combined. When a new highway or the improvement of an existing highway is planned,

the planning must be based on a land use plan meeting the requirements of the Land Use

and Building Act. Road planning phases are connected to land use planning as follows:

At the feasibility study phase, the necessity and timing of road projects are studied

at the same approximate planning level as the regional land use plan and the

local master plan.

Preliminary engineering planning corresponds to land use planning on the level

of a local master plan or a local detailed plan. A preliminary engineering plan

determines the approximate location and space requirement of the road and its

relation to the surrounding environment.

Final engineering planning is planning at the same level of detail as local land use

plans.

Construction planning is related to the implementation of a road project and is

performed before and during construction.

In different phases of the planning process, alternatives are reduced as road planning becomes

more accurate. As the process progresses, planning can be more and more focused. For the

public and other parties to the planning process, it is important to participate in the planning at

the right time. Planning can also be interrupted, if sufficient reasons no longer exist to continue

the planning process.

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A road project is given its form and details during a planning process which becomes more and

more detailed in phases, adjusted to correspond to land use planning.

Dividing project-specific planning into phases makes specifying the order and time of road

project implementation easier.

A road project is given its form and details during a planning process which becomes more and

more detailed in phases, adjusted to correspond to land use planning.

1. Road planning

Transport system Planning:

o Transport system planning, road network planning, development

planning, location study.

o Dialog with interest groups.

o Goals for further planning.

Preliminary Engineering:

o Extensive dialog.

o Approval of the plan.

Final Engineering:

o Dialog with involved parties.

o Approval of the plan.

Construction Planning:

o Construction

2. Land Use Planning:

Regional Planning:

o Compiled and approved by the regional council. Ratified by the Ministry

of Environment

General Planning:

o Compiled and approved by the municipality. Road location is approved

in the plan.

Town Planning:

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o Compiled and approved by the municipality.

3. feasibility study:

Planning a transport system involves interactive planning of land use and traffic. Thus, a

frame- work is created for the arrangement of different traffic modes and land use.

Planning gener- ates traffic policy objectives and goals, network plans for different traffic

modes, implementation strategies for the system and assessments of the impacts. More

detailed plans for pedestrian and bicycle traffic, public transport, parking etc. are made

when needed. transport system plans have been drawn up for many urban areas and some

provinces. In smaller urban areas, the planning emphasis is usually on traffic network

planning. For various purposes, feasibility studies can have different names and content.

The most common project-specific feasibility studies are the development study, needs

assessment and development/action plan. The starting points of a feasibility study are

existing land use and current road and traffic conditions. Societal development causes

changes in travel needs and traffic conditions. These changes are examined during the

feasibility study phase and the actions required to meet the goals set for the development

of traffic conditions are planned.

The outcome of the feasibility study is a project or several projects for which preliminary

examinations have been conducted of possible alternative actions, including the related

impacts and costs. During the feasibility study, the need for interaction varies according

to the nature of the project. Participation by municipalities and regional councils are

usually emphasized during co-operation. The decision to begin planning can be made

based on the feasibility study. Such a decision consists of the road authority’s statements

con- cerning the necessity, timing and further planning of development actions. Actions

deemed necessary proceed for further development and implementation. The related

timetables are determined according to the funding available.

Outcomes of feasibility studies:

• goals

• alternatives

• approximate actions

• preliminary impact assessments

• cost forecasts

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Preliminary engineering Plan:

Preliminary engineering planning determines the approximate location of the

road, the road’s connections to the existing and future road network and land

use, basic technical and traffic solutions and the principles underlying the

prevention of negative impacts to the environment. Planning is performed at a

level of detail which ensures that the plan is technically, financially and environ-

mentally feasible. When legislation requires an environmental impact assessment

(EIA), the road project’s environmental impact is assessed according to the Act

on Environmental Impact Assessment Procedure during the preliminary

engineering planning phase. The approval decision is made on the preliminary

engineering plan. The project can then be included in near-future implementation

programmes (the Finnish Transport Agency’s operating and financial plan, the

programmes of the Centres for Economic Development, Transport and the

Environment). Because the location and quality of the highway and the

highway’s impacts on people’s living conditions and the environment are

determined in the preliminary engineering plan, this phase has the most important

effect on the road project. An approved preliminary engineering plan may limit

Preliminary engineering Plan other construction activities and impose an obli-

gation on the road authority to expropriate areas. In general, principles approved

in the preliminary engineering plan are usually no longer discussed in the final

engineering planning phase. Custom- arily, when the final engineering plan is

eventually submitted for processing, solutions already approved in principle are

no longer subject to change through objections or appeals.

outcomes of preliminary engineering planning:

• approximate location of the road

• basic traffic and road engineering solutions

• principles underlying the landscaping of the road side and the handling of

green areas

• principles underlying the prevention of negative impacts on the environment

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• impact assessment

• cost estimate

• target timetable and stages of construction

Final engineering Plan:

Final engineering planning determines the precise location of the highway, areas

required for the highway, intersections of highways and private roads and

solutions for other road connections, solutions for pedestrian and bicycle traffic

and public transport, and other detailed solutions such as measures necessary to

the prevention of negative traffic impacts. Because the final engineering plan

settles all issues directly affecting land owners and other parties concerned,

interaction is focused on issues to be agreed with them. The approval decision is

made on the final engineering plan, allowing the road authority the right to take

possession of the area required for the highway. It is sometimes necessary to

make a revi- sion plan to an approved final engineering plan. This process is

similar to the original plan, unless the impact of the change is so minor that

agreement with real-estate owners is sufficient. Once financing has been ensured,

highway construction can be started.

Outcomes of final engineering planning:

precise road area

detailed solutions

cost estimate and possible division of costs

Construction Plan:

Construction planning belongs to the road construction phase and covers the

drafting of the documents required for construction. In many cases, the contractor

is often responsible for drawing up the construction plan. Within limits of the

final engineering plan, interaction between road constructors and landowners and

other concerned parties continues throughout the entire planning and construction

phase. In minor projects, the final engineering and construction planning phases

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can be combined. Compensation is paid for any damage caused to external

property during final engineering or construction planning and construction.

Outcome of construction planning:

Documents required in construction

6. Types of roads on the basis of pavement

On the basis of pavement roads can be classified into two ways:

1. Flexible pavement

2. Rigid pavement

1. Flexible pavement- Flexible pavements support loads through bearing rather than flexural action. They comprise several layers of carefully selected materials designed to gradually distribute loads from the pavement surface to the layers underneath. The design ensures the load transmitted to each successive layer does not exceed the layer’s load-bearing capacity. A typical flexible pavement section is shown in Figure 1. Figure 2 depicts the distribution of the imposed load to the subgrade. The various layers composing a flexible pavement and the functions they perform are described below:

a) Bituminous Surface (Wearing Course). The bituminous surface, or wearing course, is made up of a mixture of various selected aggregates bound together with asphalt cement or other bituminous binders. This surface prevents the penetration of surface water to the base course; provides a smooth, well-bonded surface free from loose particles, which might endanger aircraft or people; resists the stresses caused by aircraft loads; and supplies a skid-resistant surface without causing undue wear on tires.

b) Base Course. The base course serves as the principal structural component of the flexible pavement. It distributes the imposed wheel load to the pavement foundation, the subbase, and/or the subgrade. The base course must have sufficient quality and thickness to prevent failure in the subgrade and/or subbase, withstand the stresses produced in the base itself, resist vertical pressures that tend to produce consolidation and result in distortion of the surface course, and resist volume changes caused by fluctuations in its moisture content. The materials composing the base course are select hard and durable aggregates, which generally fall into two main classes: stabilized and granular. The stabilized bases normally consist of crushed or uncrushed aggregate bound with a stabilizer, such as Portland cement or bitumen. The quality of the base course is a function of its composition, physical properties, and compaction of the material.

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c) Subbase. This layer is used in areas where frost action is severe or the subgrade soil is extremely weak. The subbase course functions like the base course. The material requirements for the subbase are not as strict as those for the base course since the subbase is subjected to lower load stresses. The subbase consists of stabilized or properly compacted granular material.

d) Frost Protection Layer. Some flexible pavements require a frost protection layer. This layer functions the same way in either a flexible or a rigid pavement.

e) Subgrade. The subgrade is the compacted soil layer that forms the foundation of the pavement system. Subgrade soils are subjected to lower stresses than the surface, base, and subbase courses. Since load stresses decrease with depth, the controlling subgrade stress usually lies at the top of the subgrade. The combined thickness of subbase, base, and wearing surface must be great enough to reduce the stresses occurring in the subgrade to values that will not cause excessive distortion or displacement of the subgrade soil layer.

Fig 1: Typical flexible pavement structure

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Fig 2: Distribution of load stress in flexible pavement

2. Rigid pavement- Rigid pavements normally use Portland cement concrete as the prime structural element. Depending on conditions, engineers may design the pavement slab with plain, lightly reinforced, continuously reinforced, prestressed, or fibrous concrete. The concrete slab usually lies on a compacted granular or treated subbase, which is supported, in turn, by a compacted subgrade. The subbase provides uniform stable support and may provide subsurface drainage. The concrete slab has considerable flexural strength and spreads the applied loads over a large area. Figure 1 illustrates a typical rigid pavement structure. Rigid pavements have a high degree of rigidity. Figure 2 show how this rigidity and the resulting beam action enable rigid pavements to distribute loads over large areas of the subgrade. Better pavement performance requires that support for the concrete slab be uniform. Rigid pavement strength is most economically built into the concrete slab itself with optimum use of low-cost materials under the slab.

Fig 1: Typical rigid pavement structure

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Fig 2: Transfer of wheel load to foundation in rigid pavement structure

a) Concrete Slab (Surface Layer). The concrete slab provides structural support to the aircraft, provides a skid-resistant surface, and prevents the infiltration of excess surface water into the subbase.b) Subbase. The subbase provides uniform stable support for the pavement slab. The subbase also serves to control frost action, provide subsurface drainage, control swelling of subgrade soils, provide a stable construction platform for rigid pavement construction, and prevent mud pumping of fine-grained soils. Rigid pavements generally require a minimum subbase thickness of 4 inches (100 mm).c) Stabilized Subbase. All new rigid pavements designed to accommodate aircraft weighing 100,000 pounds (45,000 kg) or more must have a stabilized subbase. The structural benefit imparted to a pavement section by a stabilized subbase is reflected in the modulus of subgrade reaction assigned to the foundation.d) Frost Protection Layer. In areas where freezing temperatures occur and where frost-susceptible soil with a high ground water table exists, engineers must consider frost action when designing pavements. Frost action includes both frost heave and loss of subgrade support during the frost-melt period. Frost heave may cause a portion of the pavement to rise because of the nonuniform formation of ice crystals in a frost-susceptible material (see Figure 3). Thawing of the frozen soil and ice crystals may cause pavement damage under loads. The frost protection layer functions as a barrier against frost action and frost penetration into the lower frost-susceptible layers.

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Fig 3: Formation of ice crystals in frost-susceptible soil

e) Subgrade. The subgrade is the compacted soil layer that forms the foundation of the pavement system. Subgrade soils are subjected to lower stresses than the surface and subbase courses. These stresses decrease with depth, and the controlling subgrade stress is usually at the top of the subgrade unless unusual conditions exist. Unusual conditions, such as a layered subgrade or sharply varying water content or densities, may change the locations of the controlling stress. The soils investigation should check for these conditions. The pavement above the subgrade must be capable of reducing stresses imposed on the subgrade to values that are low enough to prevent excessive distortion or displacement of the subgrade soil layer.Since sub grade soils vary considerably, the interrelationship of texture, density, moisture content, and strength of sub grade material is complex. The ability of a particular soil to resist shear and deformation will vary with its density and moisture content. In this regard, the soil profile of the sub grade requires careful examination. The soil profile is the vertical arrangement of layers of soils, each of which may possess different properties and conditions.

Soil conditions are related to the ground water level, presence of water-bearing strata, and the properties of the soil, including soil density, particle size, moisture content, and frost penetration. Since the sub grade soil supports the pavement and the loads imposed on the pavement surface, it is critical to examine soil conditions to determine their effect on grading and paving operations and the need for under drains.

7. Design of flexible pavement

The designing of flexible pavement is based on a Mechanistic Empirical approach, which considered the design life of pavement to last till the fatigue cracking in bituminous surface extended to 20 per cent of the pavement surface area or rutting in the pavement reached the terminal rutting of 20 mm, whichever happened earlier.

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The Guidelines recommend that the following aspects should be given consideration while designing to achieve better performing pavements:

(i) Incorporation of design period of more than fifteen years.(ii) Computation of effective CBR of subgrade for pavement

design.(iii) Use of rut resistant surface layer.(iv) Use of fatigue resistant bottom bituminous layer. (v) Selection of surface layer to prevent top down cracking.(vi) Use of bitumen emulsion/foamed bitumen treated Reclaimed

Asphalt Pavements in base course. (vii) Consideration of stabilized sub-base and base with locally

available soil and aggregates. (viii) Design of drainage layer. (ix) Computation of equivalent single axle load considering

(a) single axle with single wheels

(b) single axle with dual wheels

(c) tandem axle and

(d) tridem axles.

(x) Design of perpetual pavements with deep strength bituminous layer.

7.1 Design for traffic- The recommended method considers design traffic in terms of the cumulative number of standard axles (80 kN) to be carried by the pavement during the design life. Axle load spectrum data are required where cementitious bases are used for evaluating the fatigue damage of such bases for heavy traffic. Following information is needed for estimating design traffic:

(i) Initial traffic after construction in terms of number of Commercial Vehicles per day (CVPD).

(ii) Traffic growth rate during the design life in percentage.

(iii) Design life in number of years.

(iv) Spectrum of axle loads.

(v) Vehicle Damage Factor (VDF).

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(vi) Distribution of commercial traffic over the carriageway.

Only the number of commercial vehicles having gross vehicle weight of 30 kN or more and their axle-loading is considered for the purpose of design of pavement. 4.1.3 Assessment of the present day average traffic should be based on seven-day-24-hour count made in accordance with IRC: 9-1972 “Traffic Census on Non-Urban Roads”.

7.2 Traffic Growth Rate

The present day traffic has to be projected for the end of design life at growth rates (‘r’) estimated by studying and analyzing the following data:

(i) The past trends of traffic growth; and

(ii) Demand elasticity of traffic with respect to macro-economic parameters (like GDP or SDP) and expected demand due to specific developments and land use changes likely to take place during design life.

If the data for the annual growth rate of commercial vehicles is not available or if it is less than 5 per cent, a growth rate of 5 per cent should be used (IRC:SP:84-2009).

7.3 Design Life

The design life is defined in terms of the cumulative number of standard axles in msa that can be carried before a major strengthening, rehabilitation or capacity augmentation of the pavement is necessary.

It is recommended that pavements for National Highways and State Highways should be designed for a minimum life of 15 years. Expressways and Urban Roads may be designed for a longer life of 20 years or higher using innovative design adopting high fatigue bituminous mixes. In the light of experience in India and abroad, very high volume roads with design traffic greater than 200 msa and perpetual pavements can also be designed using the principles stated in the guidelines. For other categories of roads, a design life of 10 to 15 years may be adopted.

If stage construction is adopted, thickness of granular layer should be provided for the full design period. In case of cemented bases and sub-bases, stage construction may lead to early failure because of high flexural stresses in the cemented layer and therefore, not recommended.

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7.4 Vehicle Damage Factor

The guidelines use Vehicle Damage Factor (VDF) in estimation of cumulative msa for thickness design of pavements. In case of cemented bases, cumulative damage principle is used for determining fatigue life of cementitious bases for heavy traffic and for that spectrum of axle loads is required.

The Vehicle Damage Factor (VDF) is a multiplier to convert the number of commercial vehicles of different axle loads and axle configuration into the number of repetitions of standard axle load of magnitude 80 kN. It is defined as equivalent number of standard axles per commercial vehicle. The VDF varies with the vehicle axle configuration and axle loading.

The equations for computing equivalency factors for single, tandem and tridem axles given below should be used for converting different axle load repetitions into equivalent standard axle load repetitions. Since the VDF values in AASHO Road Test for flexible and rigid pavement are not much different, for heavy duty pavements, the computed VDF values are assumed to be same for bituminous pavements with cemented and granular bases.

Singleaxlewith single wheelon either side=( Axel load∈kN64

)4

Singleaxlewith dual wheeloneither side=( Axel load∈kN80

)4

Tandemaxlewith dual wheel oneither side=( Axel load∈kN148

)4

Tridemaxle withdual wheel oneither side=( Axel load∈kN224

)4

VDF should be arrived at carefully by carrying out specific axle load surveys on the existing roads. Minimum sample size for survey is given in Table 7.1. Axle load survey should be carried out without any bias for loaded or unloaded vehicles. On some sections, there may be significant difference in axle loading in two directions of traffic. In such situations, the VDF should be evaluated direction wise. Each direction can have different pavement thickness for divided highways depending upon the loading pattern.

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Table 7.1 Sample Size for Axle Load Survey

Total number of Commercial Vehicles per day

Minimum percentage of Commercial Traffic to be surveyed

<3000 20 per cent3000 to 6000 15 per cent>6000 10 per cent

Axle load spectrum The spectrum of axle load in terms of axle weights of single, tandem, tridem and multi-axle should be determined and compiled under various classes with class intervals of 10 kN, such as 10 kN, 20 kN and 30 kN for single, tandem and tridem axles respectively. 4.4.6 Where sufficient information on axle loads is not available and the small size of the project does not warrant an axle load survey, the default values of vehicle damage factor as given in Table 7.2 may be used.

Table 7.2 Indicative VDF Values

Initial traffic volume in terms of commercial vehicles per day

Terrain

Rolling/Plain Hilly

0-150 1.5 0.5

150-1500 3.5 1.5

More than 1500 4.5 2.5

7.5 Distribution of Commercial Traffic over the Carriageway

Distribution of commercial traffic in each direction and in each lane is required for determining the total equivalent standard axle load applications to be considered in the design. In the absence of adequate and conclusive data, the following distribution may be assumed until more reliable data on placement of commercial vehicles on the carriageway lanes are available:

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(i) Single-lane roads Traffic tends to be more channelized on single-lane roads than two-lane roads and to allow for this concentration of wheel load repetitions, the design should be based on total number of commercial vehicles in both directions.

(ii) Two-lane single carriageway roads The design should be based on 50 per cent of the total number of commercial vehicles in both directions. If vehicle damage factor in one direction is higher, the traffic in the direction of higher VDF is recommended for design.

(iii) Four-lane single carriageway roads The design should be based on 40 per cent of the total number of commercial vehicles in both directions.

(iv) Dual carriageway roads The design of dual two-lane carriageway roads should be based on 75 per cent of the number of commercial vehicles in each direction. For dual three-lane carriageway and dual four-lane carriageway, the distribution factor will be 60 per cent and 45 per cent respectively.

Where there is no significant difference between traffic in each of the two directions, the design traffic for each direction may be assumed as half of the sum of traffic in both directions. Where significant difference between the two streams exists, pavement thickness in each direction can be different and designed accordingly. For two way two lane roads, pavement thickness should be same for both the lanes even if VDF values are different in different directions and designed for higher VDF. For divided carriageways, each direction may have different thickness of pavements if the axle load patterns are significantly different.

7.6 Computation of Design Traffic

The design traffic in terms of the cumulative number of standard axles to be carried during the design life of the road should be computed using the following equation:

N = 365×[(1+r)n –1]

r × A × D × F

Where,

N = Cumulative number of standard axles to be catered for in the design in terms of msa.

A = Initial traffic in the year of completion of construction in terms of the number of Commercial Vehicles Per Day (CVPD).

D = Lane distribution factor (as explained in para 7.5.)

F = Vehicle Damage Factor (VDF). n = Design life in years.

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r = Annual growth rate of commercial vehicles in decimal (e.g., for 5 per cent annual growth rate, r = 0.05). The traffic in the year of completion is estimated using the following formula:

A =P(1+r )x

Where,

P = Number of commercial vehicles as per last count.

x = Number of years between the last count and the year of completion of construction

7.7 Pavement Composition

When a road is built, the surface is dug-out down to the designed depth of the intended road. Preparation is carried out on the ground now exposed below (such as compaction). The road itself will then be built up above, usually consisting of four layers: -

--------------------------------------Surface Course--------------------------------------Binder Course--------------------------------------Base--------------------------------------Sub - Base--------------------------------------Capping- - - - - - - - - - - - - - - - Sub – Grade

FlexibleRoadStructure

The sub-grade is the ground below the road layers which is exposed once the ground has been dug out ready to build the road. The top level of this is termed the formation.

The capping is a layer added above the sub-grade to protect it in new constructions. In this case, the top layer of the capping will constitute the formation.

The four (typically) layers of the road above are termed (bottom to top) sub-base, base (formerly known as roadbase), base (formerly known as roadbase), binder course (formerly known as basecourse) and surface course (formerly known as wearing course).

As the stress transmitted through the road structure from the vehicles above spreads and lessens with depth, stronger and more expensive materials are needed in the upper levels. Additionally, the nearer the surface, the flatter the profile must be. This is obviously because an uneven surface will be uncomfortable for vehicle occupants and will wear more quickly (each time a vehicle hits a bump, it is in effect hammering the surface). These factors are the main reasons for the layered construction of the road.Weight on any unbound material will compact it down with

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time, as material is forced down and fills gaps. For this reason during construction of each layer, artificial compaction is carried out. In fact, each of the layers of the road structure are usually laid in layers themselves, with further compaction taking place each time. The life time of a road can be reduced by greater than expected increase in traffic, though a certain amount of traffic growth is allowed for when the road is designed. The only factor taken into account here is the expected amount of commercial vehicles. This is because the damaging effect of an 8200kg axle load is 100 times that of a 2700kg axle load, even the latter being greatly more than the axle load of a private vehicle.

The Sub-baseThe sub-base should be laid as soon as possible after final stripping to formation level, to prevent damage from

rain or sun baking which could cause surface cracks. The fact that this is required when roads are constructed,

emphasises the importance of backfilling excavations quickly and properly and preventing ingress of moisture

when roads have been excavated for utility works.

The most commonly used material for use in sub-bases is termed Type 1. This is an unbound material made

from crushed rock, crushed slag, crushed concrete, recycled aggregates or well burnt non-plastic shale. It

contains particles of various sizes, the percentage of each size being within a defined range. Up to 10% may be natural sand. The predefined and calculated range of material sizes contained means that once compacted, it

will resist further movement within its structure. In other words, it tends not to sink with time (though it will

sink if not compacted properly when laid).

Other materials used for the construction of sub-bases include bituminous-bound materials and concrete and

cement-bound materials, including wet-lean concrete.

Sub-base and Base materialsAgain, Type 1 is most commonly used. Other materials include Type 2 and Type 3. Slag bound material used

to be known as Wet Mix. It is a plant manufactured granular aggregate. It must be laid and compacted quickly,

as this must take place within 6 hours of the GBS and activator components. Various other materials are less commonly used.

All materials on arrival from the plant must be protected from the weather, as drying or wetting changes the composition. They must be spread evenly. They are laid in layers of 110mm - 225mm compacted thickness, the thickness of the layers being gauged by various means including pegs and lines, sight rails and a guide wire. In initial build and reinstatement, the thickness of the layers depends on the compaction plant being used.

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Bituminous base materials are either dense base macadam or rolled asphalt. Various concrete and cement –

bound materials are used, the specifications for these being different to those applying for sub-base materials.SurfacingBoth the surface course and binder course are included in the part of the road structure termed the surfacing. Occasionally the surfacing is laid as a single course. Normally, it is layed as two course binder and surface.

The binder course helps distribute the load of traffic above onto the base course, which is usually a weaker

material. It also provides a flat surface onto which the normally thinner surface course is laid. In new

construction, typical thickness is between 45mm and 105mm. Thickness may vary considerably where a new

binder course is laid to an existing road structure for strengthening purposes. Stone sizes used are 20, 28 or

40mm. The thicker the binder course, the larger the stone size. Materials used include open graded macadam,

dense coated macadam and rolled asphalt.Surface courses are laid in a wide range of bituminous materials,

ranging in thickness from 20 to 40mm. The material selected is dependent on the anticipated traffic intensity.

Hot rolled asphalt is made with high fines and asphaltic cement content with crushed rock, slag or gravel added. Normal thickness is 40mm with 20mm coated chippings rolled into the surface providing better skid resistance.

Stone mastic asphalt is not as susceptible to rutting as other surfaces and reduces surface noise. Normal layer

thickness is between 20mm and 40mm.

Drainage

DRAINAGE is VERY! VERY! VERY! IMPORTANT, both in relation to road pavement construction

and maintenance.

Good drainage will help to keep the water table (and strength) of the road pavement in equilibrium. Water below the road pavement must be kept low and not be allowed to rise up into the

construction layers

The road pavement must be constructed so that it will drain in the event of a failure of the integrity of the

surfacing layers, i.e. if water is able to enter the road pavement there must be a path for it to exit.

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Important of surface drainage

Softening the road surface when it is constructed of soil or sand-clay or gravel or water bound macadam

Washing out unprotected areas of the top surface, erosion of side slopes forming gullies, erosion of side drain

Generally softening of the ground giving rise to land slides or slips Softening the subgrade soil and decreasing its bearing power

Components of surface drainage

Shoulder slope Roadside drain/ shoulder drain Toe drain Bench and Berm drain Interceptor drain Out fall drain Median Drain Kerb drain

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Camber

Camber or cant is the cross slope provided to raise middle of the road surface in the transverse direction to

drain o rain water from road surface. The objectives of providing camber are:

Surface protection especially for gravel and bituminous roads

Sub-grade protection by proper drainage

Quick drying of pavement which in turn increases safety

Too steep slope is undesirable for it will erode the surface. Camber is measured in 1 in n or n% (Eg. 1 in 50 or

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2%) and the value depends on the type of pavement surface. The values suggested by IRC for various categories

of pavement is given in Table 12:1 The common types of camber are parabolic, straight, or combination of them as shown below:

Friction:

Friction between the wheel and the pavement surface is a crucial factor in the design of horizontal curves andthus the safe operating speed. Further, it also a_ect the acceleration and deceleration ability of vehicles. Lackof adequate friction can cause skidding or slipping of vehicles._ Skidding happens when the path traveled along the road surface is more than the circumferential movementof the wheels due to friction_ Slip occurs when the wheel revolves more than the corresponding longitudinal movement along the road.Various factors that a_ect friction are:_ Type of the pavement (like bituminous, concrete, or gravel),_ Condition of the pavement (dry or wet, hot or cold, etc),_ Condition of the tyre (new or old), and_ Speed and load of the vehicle.The frictional force that develops between the wheel and the pavement is the load acting multiplied by a factorcalled the coe_cient of friction and denoted as f. The choice of the value of f is a very complicated issue since

it depends on many variables. IRC suggests the coe_cient of longitudinal friction as 0.35-0.4 depending on the speed and coe

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cient of later friction as 0.15. The former is useful in sight distance calculation and the

latter in horizontal curve design.

Unevenness:

It is always desirable to have an even surface, but it is seldom possible to have such one. Even if a road is

constructed with high quality pavers, it is possible to develop unevenness due to pavement failures. Unevenness

aect the vehicle operating cost, speed, riding comfort, safety, fuel consumption and wear and tear of tyres.

Unevenness index is a measure of unevenness which is the cumulative measure of vertical undulation of

the pavement surface recorded per unit horizontal length of the road. An unevenness index value less than 1500

mm/km is considered as good, a value less than 2500 mm.km is satisfactory up to speed of 100 kmph and values

greater than 3200 mm/km is considered as uncomfortable even for 55 kmph.

Light refelection_ White roads have good visibility at night, but caused glare during day time._ Black roads has no glare during day, but has poor visibility at night_ Concrete roads has better visibility and less glareIt is necessary that the road surface should be visible at night and refelection of light is the factor that answers it.

8. Surveying Equipments used

Auto level

Automatic level is an optical instrument used to establish or check points in the same horizontal plane. It is used in surveying and building to transfer, measure, or set horizontal levels.

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Total Station

A total station is an electronic/optical instrument used in modern surveying and building

construction. The total station is an electronic theodolite (transit) integrated with an

electronic distance meter (EDM) to read slope distances from the instrument to a particular

point.

Robotic total stations allow the operator to control the instrument from a distance via remote

control. This eliminates the need for an assistant staff member as the operator holds the

reflector and controls the total station from the observed point.

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feGraderA grader, also commonly referred to as a road grader, a blade, a maintainer, or a motor grader, is a construction machine with a long blade used to create a flat surface during the grading process. Typical models have three axles, with the engine and cab situated above the rear axles at one end of the vehicle and a third axle at the front end of the vehicle, with the blade in between. In civil engineering, the grader's purpose is to "finish grade" (to refine or set precisely) the "rough grading" performed by heavy equipment or engineering vehicles such as scrapers and bulldozers. Graders are also used to set native soil foundation pads to finish grade prior to the construction of large buildings. Graders can produce inclined surfaces, to give cant(camber) to roads. In some countries they are used to produce drainage ditches with shallow V-shaped cross-sections on either side of highways.

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Excavator

Excavators are heavy construction equipment consisting of a boom, stick, bucket and cab on a rotating platform known as the "house. The house sits atop an undercarriage with tracks or wheels. A cable-operated excavator uses winches and steel ropes to accomplish the movements. They are a natural progression from the steam shovels and often called power shovels. All movement and functions of a hydraulic excavator are accomplished through the use of hydraulic fluid, with hydraulic cylinders and hydraulic motors. Due to the linear actuation of hydraulic cylinders, their mode of operation is fundamentally different from cable-operated excavators.

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Compactor

A compactor is a machine or mechanism used to reduce the size of waste material or soil

through compaction. A trash compactor is often used by a home or business to reduce the

volume of trash.Normally powered by hydraulics, compactors take many shapes and sizes.

In landfill sites for example, a large bulldozer with spiked wheels called a landfill compactor is

used to drive over waste deposited by waste collection vehicles (WCVs).

9. Testing of materiala. TESTS FOR CONCRETE:

a) CONCRETE TESTING MACHINE:

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Aim: To determine the compressive strength of concrete specimens as per IS: 516 - 1959.

APPARATUS:

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AGE AT TEST

Tests should be done at recognized ages of the test specimens, usually being 7 and 28 days. The ages should be calculated from the time of the addition of water to the drying of ingredients.

NUMBER OF SPECIMENS

At least three specimens, preferably from different batches, should be taken for testing at each selected age.

PROCEDURE:

i) The specimens, prepared according to IS: 516 - 1959 and stored in water, should be tested immediately on removal from the water and while still in wet condition. Specimens when received dry should be kept in water for 24hrs. Before they are taken for testing. The dimensions of the specimens, to the nearest 0.2mm and their weight should be noted before testing.

ii) The bearing surfaces of the compression testing machine should be wiped clean and any loose sand or other material removed from the surfaces of the specimen, which would be in contact with the compression platens.

iii) In the case of cubical specimen, the specimen should be placed in the machine in such a manner that the load could be applied to the opposite sides of the cubes, not to the top and the bottom. The axis of the specimen should be carefully aligned with the centre of thrust of the spherically seated platen. No packing should be used between the faces of the test specimen and the steel platen of the testing machine. As the spherically seated block is brought to rest on the specimen, the movable portion should be rotated gently by hand so that uniform seating is obtained.

iv)The load should be applied without shock and increased continuously at a rate of approximately 140kg/sq.cm/minute until the resistance of the specimen to the increasing load breaks down and no greater load can be sustained. The maximum load applied to the specimen should then be recorded and the appearance of the concrete and any unusual features in the type

of failure should be noted.

CALCULATION

The measured compressive strength of the specimen should be calculated by dividing the maximum load applied to the specimen during the test by the cross - sectional area calculated from the mean dimensions of the section and should be expressed to the nearest kg/sq.cm. An

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average of three values should be taken as the representative of the batch, provided the individual variation is not more than ±15% of the average. Otherwise repeat tests should be done.

REPORTING OF RESULTS

The following information should be included in the report on each test specimen:

i) Identification mark

ii) Date of test

iii) Age of specimen

iv) Curing conditions, including date of manufacture of specimen

v) Weight of specimen

vi) Dimensions of specimen

vii) Cross-sectional area

viii) Maximum load

ix) Compressive strength

x) Appearance of fractured faces of concrete and type of fracture, if unusual.

b) CALIFORNIA BEARING RATIO:

As per IS-2720 part 16

The ratio expressed in percentage of force per unit area required to penetrate a soil mass with a circular plunger of 50 mm diameter at the rate of 1’25 mm/min to that required for corresponding penetration in a standard material. The ratio is usually determined for penetration of 2’5 and 5 mm. Where the ratio at 5 mm is consistently higher than that at 2’5 mm, the ratio at 5 mm is

used. To evaluate the stability of soil sub grade and other flexible pavement materials.

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NEED & SCOPE:

The california bearing ratio test is penetration test meant for the evaluation of subgrade strength of roads and pavements. The results obtained by these tests are used with the empirical curves to determine the thickness of pavement and its component layers. This is the most widely used method for the design of flexible pavement.

This instruction sheet covers the laboratory method for the determination of C.B.R. of undisturbed and remoulded /compacted soil specimens, both in soaked as well as unsoaked state

Apparatus:

1 Moulds with Base Plate, Stay Rod and Wing Nut - These shall conform to 4.1, 4.3 and 4.4 of IS : 9669 - 19801.

2 Collar - It shall conform to 4.2 of IS : 9669 - 1980$.

3 Spacer Disc - It shall conform to 4.4 of IS : 9669 - 1980$.

4 Metal Rammer - As specified in IS : 9198 - 19795.

5 Expansion Measuring Apparatus - The adjustable stem with perforated plates and tripod shall conform to 4.4 of IS : 9669 - 1980$.

6 Weights - This shall conform to 4.4 of IS : 9669 - 1480$.

7 Loading Machine - With a capacity of at least 5 000 kg and equipped with a movable head or base which enables the plunger to penetrate into the specimen at a deformation rate of 1’25 mm/min- The machine shall be equipped with a load machine device that can read to suitable accuracy.

NOTE - In the machine priming ring can also be used.

8 Penetration Plunger - This shall conform to 4.4 of IS : 9669 - 1980*.

9 Dial Gauges - Two dial gauges reading to 0’01 mm.

10 Sieves - 47’5 mm IS Sieve and 19 mm IS Sieve [ see IS : 460 ( Part 1 ) - 1985: I.

PREPARATION OF TEST SPECIMEN

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The test may be performed on undisturbed specimens and on remoulded specimens which may be compacted either statically or dynamically.

Undisturbed specimen

Attach the cutting edge to the mould and push it gently into the ground. Remove the soil from the outside of the mould which is pushed in . When the mould is full of soil, remove it from weighing the soil with the mould or by any field method near the spot.

Determine the density

Remoulded specimen

Prepare the remoulded specimen at Proctors maximum dry density or any other density at which C.B.R> is required. Maintain the specimen at optimum moisture content or the field moisture as required. The material used should pass 20 mm I.S. sieve but it should be retained on 4.75 mm I.S. sieve. Prepare the specimen either by dynamic compaction or by static compaction.

Dynamic Compaction

Take about 4.5 to 5.5 kg of soil and mix thoroughly with the required water.

Fix the extension collar and the base plate to the mould. Insert the spacer disc over the base (See Fig.38). Place the filter paper on the top of the spacer disc.

Compact the mix soil in the mould using either light compaction or heavy compaction. For light compaction, compact the soil in 3 equal layers, each layer being given 55 blows by the 2.6 kg rammer. For heavy compaction compact the soil in 5 layers, 56 blows to each layer by the 4.89 kg rammer.

Remove the collar and trim off soil.

Turn the mould upside down and remove the base plate and the displacer disc.

Weigh the mould with compacted soil and determine the bulk density and dry density.

Put filter paper on the top of the compacted soil (collar side) and clamp the perforated base plate on to it.

Static compaction

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Calculate the weight of the wet soil at the required water content to give the desired density when occupying the standard specimen volume in the mould from the expression.

W =desired dry density * (1+w) V

Where W = Weight of the wet soil

w = desired water content

V = volume of the specimen in the mould = 2250 cm3 (as per the mould available in laboratory)

Take the weight W (calculated as above) of the mix soil and place it in the mould.

Place a filter paper and the displacer disc on the top of soil.

Keep the mould assembly in static loading frame and compact by pressing the displacer disc till the level of disc reaches the top of the mould.

Keep the load for some time and then release the load. Remove the displacer disc.

The test may be conducted for both soaked as well as unsoaked conditions.

If the sample is to be soaked, in both cases of compaction, put a filter paper on the top of the soil and place the adjustable stem and perforated plate on the top of filter paper.

Put annular weights to produce a surcharge equal to weight of base material and pavement expected in actual construction. Each 2.5 kg weight is equivalent to 7 cm construction. A minimum of two weights should be put.

Immerse the mould assembly and weights in a tank of water and soak it for 96 hours. Remove the mould from tank.

Note the consolidation of the specimen.

Procedure for Penetration Test

Place the mould assembly with the surcharge weights on the penetration test machine.

Seat the penetration piston at the center of the specimen with the smallest possible load, but in no case in excess of 4 kg so that full contact of the piston on the sample is established.

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Set the stress and strain dial gauge to read zero. Apply the load on the piston so that the penetration rate is about 1.25 mm/min.

Record the load readings at penetrations of 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 4.0, 5.0, 7.5, 10 and 12.5 mm. Note the maximum load and corresponding penetration if it occurs for a penetration less than 12.5 mm.

Detach the mould from the loading equipment. Take about 20 to 50 g of soil from the top 3 cm layer and determine the moisture content.

c) SLUMP TEST:

As per IS: 1199Slump Test is done to determine the workability of fresh concrete.APPARATUS:i) Slump coneii) Tamping rod

PROCEDUREi) The internal surface of the mould is thoroughly cleaned and applied with a light coat of oil.ii) The mould is placed on a smooth, horizontal, rigid and non- absorbent surface.iii) The mould is then filled in four layers with freshly mixed concrete, each approximately to one-fourth of the height of the mould.iv) Each layer is tamped 25 times by the rounded end of the tamping rod (strokes are distributed evenly over the cross- section).v) After the top layer is rodded, the concrete is struck off the level with a trowel.

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vi) The mould is removed from the concrete immediately by raising it slowly in the vertical direction.vii) The difference in level between the height of the mould and that of the highest point of the subsided concrete is measured.viii) This difference in height in mm is the slump of the concrete.

REPORTING OF RESULTSThe slump measured should be recorded in mm of subsidence of the specimen during the test. Any slump specimen which collapses or shears off laterally gives incorrect result and if this occurs, the test should be repeated with another sample. If in the repeat test also, the specimen shears, the slump should be measured and the fact that the specimen sheared, should be recorded.

Procedure:i. To obtain a representative sample, take samples from two or more regular

intervals throughout the discharge of the mixer or truck. DO NOT take samples at the beginning or the end of the discharge.

ii. Dampen inside of cone and place it on a smooth, moist, non-absorbent, level surface large enough to accommodate both the slumped concrete and the slump cone. Stand or, foot pieces throughout the test procedure to hold the cone firmly in place.

iii. Fill cone 1/3 full by volume and rod 25 times with 5/8-inch- diameter x 24-inch-long hemispherical tip steel tamping rod. (This is a specification requirement which will produce non- standard results unless followed exactly.) Distribute rodding evenly over the entire cross section of the sample.

iv. Fill cone 2/3 full by volume. Rod this layer 25 times with rod penetrating into, but not through first layer. Distribute rodding evenly over the entire cross section of the layer.

v. Fill cone to overflowing. Rod this layer 25 times with rod penetrating into but not through, second layer. Distribute rodding evenly over the entire cross section of this layer.

vi. Remove the excess concrete from the top of the cone, using tamping rod as a screed. Clean overflow from base of cone.

vii. Immediately lift cone vertically with slow, even motion. Do not jar the concrete or tilt the cone during this process. Invert the withdrawn cone,

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and place next to, but not touching the slumped concrete. (Perform in 5-10 seconds with no lateral or torsional motion.)

viii. Lay a straight edge across the top of the slump cone. Measure the amount of slump in inches from the bottom of the straight edge to the top of the slumped concrete at a point over the original center of the base. The slump operation shall be completed in a maximum elapsed time of 2 1/2 minutes. Discard concrete. DO NOT use in any other tests.

d) AGGREGATE IMPACT VALUE:The Impact value is determined as per IS: 2386 (Part IV) - 1963.APPARATUSImpact testing machine conforming to IS: 2386 (Part IV) - 1963ii) IS Sieves of sizes - 12.5mm, 10mm and 2.36mmiii) A cylindrical metal measure of 75mm dia. and 50mm depthiv) A tamping rod of 10mm circular cross section and 230mm length, rounded at one endv) Oven

PREPARATION OF SAMPLEi) The test sample should conform to the following grading:- Passing through 12.5mm IS Sieve 100%- Retention on 10mm IS Sieve 100%ii) The sample should be oven-dried for 4hrs. at a temperature of 100 to 110˚C and cooled.iii) The measure should be about one-third full with the prepared aggregates and tamped with 25 strokes of the tamping rod. A further similar quantity of aggregates should be added and a further tamping of 25 strokes given. The measure should finally be filled to overflow, tamped 25 times and the surplus aggregates struck off, using a tamping rod as a

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straight edge. The net weight of the aggregates in the measure should be determined to the nearest gram (Weight 'A').

PROCEDUREi) The cup of the impact testing machine should be fixed firmly in position on the base of the machine and the whole of the test sample placed in it and compacted by 25 strokes of the tamping rod.ii) The hammer should be raised to 380mm above the upper surface of the aggregates in the cup and allowed to fall freely onto the aggregates. The test sample should be subjected to a total of 15 such blows, each being delivered at an interval of not less than one second.

REPORTING OF RESULTSi) The sample should be removed and sieved through a 2.36mm IS Sieve. The fraction passing through should be weighed (Weight 'B'). The fraction retained on the sieve should also be weighed (Weight 'C') and if the total weight (B+C) is less than the initial weight (A) by more than one gram, the result should be discarded and a fresh test done.ii) The ratio of the weight of the fines formed to the total sample weight should be expressed as a percentage.B Aggregate impact value = ——– x 100% Aiii) Two such tests should be carried out and the mean of the results should be reported.A sample proforma for the record of the test results is given in Annexure-III.

b. TESTS FOR CEMENT:Vicat apparatus:To determine the initial and the final setting time of cement as per IS: 4031 (Part 5) – 1988APPARATUSi) Vicat apparatus conforming to IS: 5513 - 1976ii) Balance, whose permissible variation at a load of 1000g should be +1.0giii) Gauging trowel conforming to IS: 10086 - 1982

PROCEDUREi) Prepare a cement paste by gauging the cement with 0.85 times the water required to give a paste of standard consistency (see Para 1.2).ii) Start a stop-watch, the moment water is added to the cement.iii) Fill the Vicat mould completely with the cement paste gauged as above, the mould resting on a non-porous plate and smooth off the surface of the paste making it level with the top of the mould. The cement block thus prepared in the mould is the test block.

A) INITIAL SETTING TIME

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Place the test block under the rod bearing the needle. Lower the needle gently in order to make contact with the surface of the cement paste and release quickly, allowing it to penetrate the test block. Repeat the procedure till the needle fails to pierce the test block to a point 5.0 ± 0.5mm measured from the bottom of the mould.The time period elapsing between the time, water is added to the cement and the time, the needle fails to pierce the test block by 5.0 ± 0.5mm measured from the bottom of the mould, is the initial setting time.

B) FINAL SETTING TIMEReplace the above needle by the one with an annular attachment.The cement should be considered as finally set when, upon applying the needle gently to the surface of the test block, the needle makes an impression therein, while the attachment fails to do so. The period elapsing between the time, water is added to the cement and the time, the needle makes an impression on the surface of the test block,

while the attachment fails to do so, is the final setting time.REPORTING OF RESULTSThe results of the initial and the final setting time should be reported to the nearest five minutes.

c. TESTS FOR BITUMEN:i. Marshall’s Stability Test: To determine the Marshall stability of bituminous

mixture as per ASTM D 1559

PRINCIPLEMarshall stability is the resistance to plastic flow of cylindrical specimens of a bituminous mixture loaded on the lateral surface. It is the load carrying capacity of the mix at 60˚C and is measured in kg.

APPARATUSi) Marshall stability apparatusii) Balance and water bath

SAMPLEFrom Marshall stability graph, select proportions of coarse aggregates, fine aggregates and filler in such a way, so as to fulfill the required specification. The

total weight of the mix should be 1200g.

PROCEDUREi) Heat the weighed aggregates and the bitumen separately upto 170˚ C and 163˚

C respectively.

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ii) Mix them thoroughly, transfer the mixed material to the compaction mould arranged on the compaction pedestal.iii) Give 75 blows on the top side of the specimen mix with a standard hammer (45cm, 4.86kg). Reverse the specimen and give 75 blows again. Take the mould with the specimen and cool it for a few minutes.iv) Remove the specimen from the mould by gentle pushing. Mark the specimen and cure it at room temperature, overnight.v) A series of specimens are prepared by a similar method with varying quantities of bitumen content, with an increment of 0.5% (3 specimens) or 1 bitumen content.vi) Before testing of the mould, keep the mould in the water bath having a temperature of 60 o C for half an hour.vii) Check the stability of the mould on the Marshall stability apparatus.

REPORTING OF RESULTSPlot % of bitumen content on the X-axis and stability in kg on the Y-axis to get maximum Marshall stability of the bitumen mix.

PENSKY - MARTENS APPARATUSTo determine the flash point and the fire point of asphaltic bitumen and fluxed native asphalt, cutback bitumen and blown type bitumen as per IS: 1209 - 1978.

PRINCIPLEFlash Point - The flash point of a material is the lowest temperature at which the application of test flame causes the vapours from the material to momentarily catch fire in the form of a flash under specified conditions of the test.Fire Point - The fire point is the lowest temperature at which the application of test flame causes the material to ignite and burn at least for 5 seconds under specified conditions of the test.

APPARATUSi) Pensky-Martens apparatusii) Thermometer- Low Range: -7 to 110 Celsius, Graduation 0.5 CelsiusHigh Range: 90 to 370 Celsius, Graduation 2 Celsius

SAMPLEThe sample should be just sufficient to fill the cup upto the mark given on it.

PROCEDUREA) FLASH POINTi) Soften the bitumen between 75 and 100˚C. Stir it thoroughly

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to remove air bubbles and water.ii) Fill the cup with the material to be tested upto the filling mark. Place it on the bath. Fix the open clip. Insert the thermometer of high or low range as per requirement and also the stirrer, to stir it.iii) Light the test flame, adjust it. Supply heat at such a rate that the temperature increase, recorded by the thermometer is neither less than 5˚C nor more than 6˚C per minute.iv) Open flash point is taken as that temperature when a flash first appears at any point on the surface of the material in the cup. Take care that the bluish halo that sometimes surrounds the test flame is not confused with the true flash. Discontinue the stirring during the application of the test flame.v) Flash point should be taken as the temperature read on the thermometer at the time the flash occurs.

B) FIRE POINTi) After flash point, heating should be continued at such a rate that the increase in temperature recorded by the thermometer is neither less than 5˚C nor more than 6˚C per minute.ii) The test flame should be lighted and adjusted so that it is of the size of a bead 4mm in dia.

REPORTING OF RESULTSi) The flash point should be taken as the temperature read on the thermometer at the time of the flame application that causes a distinct flash in the interior of the cup.ii) The fire point should be taken as the temperature read on the thermometer at which the application of test flame causes the material to ignite and burn for at least 5 seconds.

RING AND BALL APPARATUS

To determine the softening point of asphaltic bitumen and fluxed native asphalt, road tar, coal tar

pitch and blown type bitumen as per IS: 1205 - 1978.

PRINCIPLE

It is the temperature at which the substance attains a particular degree of softening under specified condition of the test.

APPARATUS

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i)Ring and ball apparatus

ii) Thermometer - Low Range : -2 to 80 Celsius , Graduation 0.2 Celsius

- High Range: 30 to 200 Celsius , Graduation 0.5 Celsius

PREPARATION OF SAMPLE

i) The sample should be just sufficient to fill the ring. The excess sample should be cut off by a knife.

ii) Heat the material between 75 and 100 Celsius.Stir it to remove air bubbles and water, and filter it through IS Sieve 30, if necessary.

iii) Heat the rings and apply glycerine. Fill the material in it and cool it for 30 minutes.

iv) Remove excess material with the help of a warmed, sharp knife.

PROCEDURE:

A) Materials of softening point below 80 Celsius.

i) Assemble the apparatus with the rings, thermometer and ball guides in position.

ii) Fill the beaker with boiled distilled water at a temperature 5.0 ± 0.5 o C per minute.

iii) With the help of a stirrer, stir the liquid and apply heat to the beaker at a temperature of 5.0 ± 0.5 Celsius per minute.

iv) Apply heat until the material softens and allow the ball to pass through the ring.

v) Record the temperature at which the ball touches the bottom, which is nothing but the softening point of that material.

B) Materials of softening point above 80 Celsius

The procedure is the same as described above. The only difference is that instead of water, glycerine is used and the starting temperature of the test is 35˚C.

REPORTING OF RESULTS

Record the temperature at which the ball touches the bottom.

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10. Defects in Bitumen Pavement

There are four predominant modes of distress in bituminous pavements namely:- Cracking- Deformation- Surface texture deficiencies- Potholes

10.1 Cracking Cracks are fissures resulting from partial or complete fractures of the pavement surfaceand underlying layers. They can range from isolated single cracks to a series ofinterconnected cracks spreading over the entire pavement surface.

There are a variety of factors leading to cracking of pavement surface. They include:- deformation- fatigue failure of the surfacing or pavement structure- ageing of the surfacing- reflection of movement of underlying layers- shrinkage- poor construction

The detrimental effects associated with the presence of cracks are manifold and include:- loss of waterproofing- loss of load spreading ability- pumping and loss of fines from the base course- loss of riding quality- poor aesthetics

The various types of cracks (and the page number where they are described) are:

- Block Cracks

DescriptionInterconnected cracks forming a series of large polygons. Cell sizes are usuallygreater than 200 mm and can exceed 3000mm (synonym – laddercracks, map cracks)

Attributes_ Predominant width of crack (mm)_ Predominant cell width (mm)_ Area affected (m2)

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Possible causes_ Hardening and shrinkage of bituminous mixture_ Fatigue cracking in embrittled bituminous wearing course

Recommended remedies_ Cold milling and resurfacing_ Full depth reconstruction_ Hot-in-place recycling

- Crocodile Cracks

DescriptionInterconnected or interlaced cracks forming a series of small polygons resembling a crocodile hide. Usually associated with wheel paths and with resilient subgrade. Cell sizes are generally less than 150 mm across butmay extend up to 300 mm (synonym – alligator cracks, crazing)

Attributes_ Predominant width of crack (mm)_ Predominant cell width (mm)_ Area affected (m2)

Possible causes_ Saturated base or subgrade_ Rupture of surface course due to traffic load, fatigue, ageing and brittleness of the binder_ Inadequate pavement thickness_ Developing from a surface showing block cracking

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Recommended remedies_ Full depth reconstruction – removing the wet material and installing drainage_ Deep inlay_ Hot-in-place recycling_ Skin patches or sealing with emulsion and sand can be used as a temporary repair

- Diagonal Cracks

DescriptionAn unconnected crack which generally takes a diagonal line across a pavement

Attributes_ Predominant width of crack (mm)_ Length (m)_ Area affected (m2)

Possible causes_ Reflection of a shrinkage crack or joint in and underlying cemented material_ Differential settlements between embankments, cuts or structures_ Tree roots_ Service installation

Recommended remedies

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_ Fill and seal the crack with hot bitumen or other approved crack sealant_ Cold mill and resurface

- Longitudinal Cracks

DescriptionCrack running longitudinally along the pavement. Can occur singly or as series of almost parallel cracks. Some limited branching may occur

Attributes_ Width of dominant crack (mm)_ Length of dominant crack (m)_ Spacing (mm)_ Area affected (m2)

Possible causes

(a) Occurring singly :_ Poor longitudinal joint construction_ Differential movement in the case of pavement widening_ Bitumen hardening_ Incipient slips for roads on slopes or loss of support due to adjacent deep excavation_ Reflection of cracking from joints of underlying concrete pavement

(b) Occurring as a series of almost parallel cracks :_ Volume change of expansive clay subgrade_ Differential settlement of subgrade, e.g. between cut and fill_ Incipient slips for roads on slopes or loss of support due to adjacent deep excavation

Recommended remedies_ Fill and seal the crack with hot bitumen or other approved crack sealant._ Cold mill and resurface._ Improvement of stability of the slopes._ Provision of sufficient lateral support to road excavations

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10.2 Deformation

Deformation can be conceived as any change of the road structure, which leaves the roadsurface in a shape different from the one intended. It may be due to load associated(traffic) or non-load associated (environmental) influences. Deformation is an important element of pavement condition as it affects serviceabilityand may reflect structural inadequacies. It also has significant impact of vehicleoperating costs.

10.3 Potholes Potholes are bowl-shaped depressions in the pavement surface developing from anotherdefect (cracking, delamination etc.), and resulting in allowing the entry of water and

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disintegration with removal of material by traffic over weakened spots on the surface. Possible causes_ Developing from another defect suchas too thin a surfacing layer, too many fines etc., resulting in disintegration with removal of material by traffic over weakened spots on the surface_ Moisture entry to base course through a cracked pavement surface

Recommended remedies_ Temporary repair involves cleaning the hole and filling it with either instant hole filling material or bituminous wearing course material._ Permanent repair by square patching or hot-in-place recycling.

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project report 1

Documents

project activities

total project cost

industrial training

heavy traffic

suman kumar

tarun kumar

pankaj kumar

sanjay kumar