project report on pavement design

CERTIFICATE OF DECLARATION

I hereby certify that the work which is being presented in the project report entitled “design of road pavement” by “Vivek Singh” in partial fulfilment of requirements for the award of degree of B.TECH. (Civil Engineering) submitted in the Department of CE at “RIMT-MAEC” under Punjab technical University, Jalandhar is an authentic record of my own work carried out during a period from--------------- to ------------ under the supervision of Er. Narinder Singh.

Signature of a student.

This is to certify that the above statement made by the candidate is correct to the best of my/our knowledge.

Signature of Supervisor.

The B.TECH viva-voce examination of (Rishikesh Kumar) has been held on------------ and accepted.

Signature of Supervisor.

Signature of External Examiner.

Signature of H.O.D.

__________________________________________________________________ DESIGN OF ROAD PAVEMENT

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ACKNOWLEDGEMENT

We are expressing our deep sense of gratitude to our respected H.O.D Prof. D.K.Dua, Department of Civil Engineering and our guide Er. Narinder Singh for their constant guidance, innovative, suggestion, and warm encouragement throughout the programme and preparation of this project.

We thank profusely that faculty member for their help and suggestions given during course of program. We are thankful to one and all, which help directly or indirectly in completing this project report.

We learnt more from this project and build on our carrier to success.

(Vivek Singh)


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INTRODUCTION

The transportation by road is the only road which gives maximum service to one and all. This mode had also the maximum flexibility for travel and with reference to route, direction, time and speed of travel. It is possible to provide door to door service only by road transport. Concrete pavement a larger number of advantages such as a long life span negligible maintenance, user and environmental friendly and lower-cost. Keeping in this view the whole life-cycle cost analysis for the black topping and which topping have been done based on various condition such as type of laying as single lane, two lane, four lane different traffic namely deterioration of road three categories. The highway pavement is a structure consisting of superimposed layers of processed materials above the natural soil subgrade, whose primary function is to distribute the applied vehicle loads to the subgrade. The pavement structure should be able to provide a surface of acceptable riding quality, adequate skid resistance, Favourable light reflecting characteristic, and low noise pollution. The ultimate aim is to ensure that the transmitted stresses due to wheel load are Suffice, Nightly reduced, so that they will not exceed bearing capacity of the sub low grade. Two types of pavements are generally recognised as serving this purpose, namely flexible pavements and rigid pavements. This gives an overview on pavement types, layers and their function cost analysis.

Various grades of concrete under a similar condition of traffic and design concrete road are found to more suitable than bituminous road. Since the whole life-cycle cost comes out to be lower in the range of 30% to 50% but for road having traffic less than 400cv/day and the road is in good condition, the difference between whole Life Cost of the road is very less. The initial cost of concrete overlay is 15% to 60% more than flexible overlay.

To design the road is stretch as a flexible pavement by using different flexible methods like group index method, C.B.R. method as per IRC: 37 – 2001, Triaxial method, California resistance value method, and as a rigid pavement as per IRC: for the collected design upon a given black cotton soil subgrade and to estimates the construction cost of designed pavement by each method. To propose a suitable or best methods to a given condition or problem. The main objective of this study is to develop a strategy to select the most cost if efficient pavement design method to carry out for a sections of a highway network and also to identify the cost analysis of different pavement design method.


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SCOPE OF PROJECT

This section sets out the guideline for design of road pavement to meet the required design life, based on the subgrade strength, traffic loading and environmental factors, and including the selection of appropriate materials for subgrade, sub base, base and wearing surface.

The guideline contains procedures for the design of the following forms of surfaced road pavement construction: a) Flexible pavements consisting of unbound materials; b) Flexible pavements that contain one or more bond layers, including pavements containing asphalt layers other than thin asphalt wearing surface; c) Rigid pavements (i.e. cement concrete pavements); d) Concrete or clay segmental pavements


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CONTENTS

Chapter No.

Page

1.

Pavement  Types Of Pavement  Pavement Materials 2. Flexible Pavement  Types Of Flexible Pavement  Layers Of Pavement  Failure Of Flexible Pavement 3. Rigid pavement  Type Of Rigid Pavement  Failure Of Rigid Pavement  Joints In Rigid Pavement 4. Test On Aggregate And Bitumen I. CBR Test II. Impact Test III. Crushing Strength Test IV. Penetration Test V. Los Ageless Abrasion Test Of Aggregate VI. Flash And Fire Point Of Bitumen VII. Softening Point Of Bitumen 5. Comparison Between Flexible And Rigid Pavement 6. Role Of The Stabilisation On Pavement Design  Lime Stabilisation  Cementatious Stabilisation 7. Design And Cost Analysis Of Pavement  Design Of Flexible Pavement By Group Index Method  California Resistance Value Method  Design of flexible pavement by CBR data 8. Conclusion 9. Bibliography

6 6 7 8 9 10 12 13 14 14 15 17 18 26 29 32 34 36 38 41 42 42 42 44 44 45 46 48 49

1. PAVEMENT


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The highway pavement is a structure consisting of superimposed layers of processed materials above the natural soil subgrade, whose primary function is to distribute the applied vehicle loads to the subgrade. The pavement structure should be able to provide a surface of acceptable riding quality, adequate skid resistance, Favourable light reflecting characteristic, and low noise pollution. The ultimate aim is to ensure that the transmitted stresses due to wheel load are Suffice, Nightly reduced, so that they will not exceed bearing capacity of the sub low grade. Two types of pavements are generally recognised as serving this purpose, namely flexible pavements and rigid pavements.

 TYPES OF PAVEMENT



Flexible - Pavements with a bitumen bonded surfacing and the road base.



Flexible composite - The surfacing and upper road base our bituminous on a lower road base of cement bonded material.



Rigid - Pavements with a concrete surface slab which can be unreinforced, joint reinforced or continuously reinforced.



Rigid composite - Continuously reinforced concrete slab with a bituminous overlay.

 PAVEMENT MATERIAL


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•

SOIL:Pavements are conglomeration of materials. These materials, their associated properties, and their interactions determine the properties of the resultant pavement. Thus, a good under - standing of these materials, how they are characterised, and how they perform is fundamental to understanding pavement. The materials which are used in construction of Highway are of intense interest to the highway engineer. This requires not only a through understanding of the soil and aggregate properties which effect pavement stability and durability, but also the binding materials which may be added to improve these pavement features.

•

SUB GRADE SOIL:Side is an accumulation or deposit of earth material, derived naturally from the disintegration of rocks or decay of vegetation that can be excavated readily with power equipment in the field or disintegrated by gen whole the mechanical means in the laboratory. The supporting soil beneath the pavement and its special under courses is called sub grade. Undisturbed soil beneath the pavement is called natural sub grade. Compacted sub grade is the soil contacted by controlled movement of the heavy compactors.

•

GRAVEL:These are coarse materials with particle size under 2.36 mm with little or no fines contributing to cohesion of materials.

•

MOORUM:These are products of decomposition and weathering of the pavement rock.

•

SILTS:These are finer than sand, brighter in colour as compared to clay, and exhibit little cohesion. When a lump of silty soil mixed with water, alternately squeezed and tapped Shiny surface makes its appearance, thus dilatency is a specific property of soil.

•

CLAYS:These are finer than silts. Clayey soils exhibit stickiness, high strength when dry and show no dialtency. Black cotton soil and other expensive clay exhibit swelling and shrinkage properties. Paste of clay with water when rubbed in between fingers leaves strain, which is not observed for silts.


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2. FLEXIBLE PAVEMENT

Flexible pavement will transmit wheel load stresses to the lower layers by grain to grain transfer through the points of contact in the granular structure. The wheel load acting on the pavement will be distributed to the wider area, and the stress decreases with the depth. Taking advantage of this stress distribution characteristic, flexible pavements normally has many layers. Hence the design of flexible payment uses the concept of layered system. Based on this, flexible pavement may be constructed in the number of layers and the top layer has to be of the best quality to sustain maximum compressive stress, in addition to wear and tear. The lower layer will experience lesser magnitude of stress and low quality material can be used.

Flexible payments are constructed using bituminous materials. These can be either in the form of surface treatment (such as bituminous surface treatment generally found on the low volume road is available) or, asphalt concrete surface courses, flexible payment layer reflect the deformation of lower layer on to the surface layer (e.g., if there is any undulation in sub grade then it will be transferred to the surface layer). In the case of flexible payment, the design is based on overall performance of flexible payment, and the stresses produced should be keep well below the allowable stresses of each payment layer.


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 TYPE OF FLEXIBLE PAVEMENT

The following type of construction had been used in flexible payment: 1. 2. 3. 4.

Conventional layered flexible payment. Full depth asphalt pavement. Contained rock asphalt mat (CRAM). Conventional flexible payments are layered system with high-quality expensive materials are placed in the top where stresses are high, and low quality cheap materials are placed in the lower layers. 5. Full depth asphalt pavement are constructed by placing bituminous layer directly on the soil subgrade. This is more suitable when there is high traffic and local material are not available. 6. Contained rock asphalt mats are constructed by placing Dense/open graded aggregate layers in the between two asphalts layers. Modified dense graded asphalt concrete is placed above the subgrade will significantly reduce the vertical compressive strain on the soil subgrade and protect from surface water.


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 LAYERS IN THE FLEXIBLE PAYMENT

•

SEAL COAT:-

Seal coat is a thin surface treatment used to waterproof the surface and to provide skid resistance.

•

TACK COAT:-

Tack coat is very light application of the asphalt, usually asphalt emulsion diluted with water, it provide a bonding between two layer of binder course and must be thin, uniformly cover the entire surface, and set very fast.

•

PRIME COAT:-

Prime coat is an application of low viscous cutback bitumen to an absorbent surface like granular bases on which binder layer is placed. It provide bonding between two layers. Unlike tack coat, prime coat penetrate into the layer below plugs and voids, and forms a watertight surface.

•

SURFACE COURSE:-

Surface course is the layer directly in contact with traffic loads and are generally contains superior quality materials. They are is usually constructed with dense graded asphalt concrete (AC). The function and the requirements of layer are: 

It provides characteristic such as friction, smoothness, drainage, etc. it will prevent the entrance of excessive quantities of surface water into the underlying base, sub bass and subgrade.


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

It must be tough to resist the distortion under traffic and provide a smooth and is skid resistance riding surface.

It must be waterproof to protect the entire base and subgrade from the weaking effect of water.

•

BINDER COURSE:-

This layer provides the bulk of asphalt concrete structure. it’s chief purpose is to distribute load to the base course the binder course is generally consist of aggregate having layers asphalt and they do not require quality as high as the surface course, so replacing a part of the surface course by the binder course results in the more economical design.

•

BASE COURSE:-

The base course is the layer of material immediately beneath the surface of binder course and it provides additional load distribution and contribute to the subsurface drainage it may be composed of crushed stone, crushed slag, and other untreated or a stabilised materials

•

SUB BASE COURSE:The sub base course is the layer of material beneath the base course and the primary function are to provide structural support, improve drainage, and reduce the intrusion of fines from the sub grade in the pavement structure if the base course is open graded, then the sub base course with the more fine can serve as a filler between subgrade and the base course. A sub base course is not always needed or used. For example, a pavement constructed over our high quality, estate subgrade may not need the additional feature offered by a sub base course. In such situation, sub base course maybe not be provide.

•

SUBGRADE:-

The topsoil or subgrade is a layer of natural soil prepared to receive the stresses from the layer above. It is essential that at no time soil subgrade is overstressed. It would be contacted to the desirable density, near the optimum moisture content.


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 FAILURE OF FLEXIBLE PAVEMENT

The major flexible payment failures are fatigue cracking, rutting, and the thermal cracking. The fatigue cracking of flexible payment is due to horizontal tensile strain at the bottom of the asphaltic concrete. The failure criterion relates allowable number of load repetition to the tensile strain and the relation can be determined in the laboratory fatigue test asphaltic concrete specimen. Rutting occurs only on flexible payment as indicated by the permanent information of rut depth along the wheel load path. Two design method have been used to control rutting: 1. To limit the vertical compressive strain on the top of subgrade and 2. To limit to tolerable amount (12 mm normally). Thermal cracking includes both lowtemperature cracking and thermal fatigue cracking.

•

FORMATION OF CRACKS:-

CRACKS ON FLEXIBLE PAVEMENT


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3. RIGID PAVEMENT

Rigid pavement are those which possess not worthy flexural strength or flexural rigidity .The stresses are not transferred from grain to grain to the lower layers as in the case of flexural pavement layers. The rigid pavements are made of Portland cement concrete-either plain, reinforced or pre-stressed concrete. The plain cement concrete slabs are expected to take-up about 40kg/cm2. The rigid pavement has the slab action and is capable of transmitting the wheel load stresses through a wider area below. The rigid pavement does not get deformed to the shape of the lower surface as it can bridge the minor variations of lower layers. The cement concrete pavement slab can very well serve as a wearing surface as well as effective base course. Therefore usually the rigid pavement structure consist of a cement concrete slab, below which a granular base or sub-base may be provided. The rigid pavements are usually designed and the stresses are analysed using the elastic theory

RIGID PAVEMENT


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In rigid pavement, load is distributed by the slab action, and the pavement behaves like an elastic plate resting on a viscous medium (Figure 19:4). Rigid pavements are constructed by Portland cement (PCC) and should be analysed by plate theory instead of layer theory, assuming an elastic plate resting on viscous foundation. Plate theory is a simplified version of layer theory that assumes the concrete slab as a medium thick plate which is plane before loading and to remain plane after loading Bending of the slab due to wheel load and temperature variation and the resulting tensile and flexural stress.

•

TYPES OF RIGID PAVEMENTS

Rigid pavements can be classified into four types:  Jointed plain concrete pavement (JPCP),  Jointed reinforced concrete pavement (JRCP),  Continuous reinforced concrete pavement (CRCP), and  Pre-stressed concrete pavement (PCP). Jointed Plain Concrete Pavement are plain cement concrete pavements constructed with closely spaced contraction joints. Dowel bars or aggregate interlocks are normally used for load transfer across joints. They normally has a joint spacing of 5 to 10m. Jointed Reinforced Concrete Pavement although reinforcements do not improve the structural capacity significantly, they can drastically increase the joint spacing to 10 to 30m. Dowel bars are required for load transfer. Reinforcement’s help to keep the slab together even after cracks. Continuous Reinforced Concrete Pavement Complete elimination of joints are achieved by reinforcement.

•

FAILURE OF RIGID PAVEMENTS

Fatigue cracking has long been considered as the major, or only criterion for rigid pavement design. The Allowable number of load repetitions to cause fatigue cracking depends on the stress ratio between flexural Tensile stress and concrete modulus of rupture. Of late, pumping is identified as an important failure criterion. Pumping is the ejection of soil slurry through the joints and cracks of cement concrete pavement, caused during The downward movement of slab under the heavy wheel loads. Other major types of distress in rigid pavements Include faulting, spelling, and deterioration.


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Failure of rigid pavement

•

JOINTS IN RIGID PAVEMENT

Joints are purposefully placed discontinuities in a rigid pavement surface course. The most common types of pavement joints, defined by their function, are contraction, expansion, isolation and construction.

Joints In Rigid Pavement


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•

CONTRACTION JOINTS:-

A contraction joint is a sawed, formed, or tooled groove in a concrete slab that creates a weakened vertical plane. It regulates the location of the cracking caused by dimensional changes in the slab. Unregulated cracks can grow and result in an unacceptably rough surface as well as water infiltration into the base, sub base and subgrade, which can enable other types of pavement distress. Contraction joints are the most common type of joint in concrete pavements, thus the generic term "joint" generally refers to a contraction joint.

Contraction Joints in rigid pavement

•

EXPANSION JOINTS:-

An expansion joint is placed at a specific location to allow the pavement to expand without damaging adjacent structures or the pavement itself. However, expansion joint are not typically used today because their progressive closure tends to cause contraction joints to progressively open.


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•

ISOLATION JOINTS:-

It is used to lessen compressive stresses that develop at t- and unsymmetrical intersections, ramps, bridges, building foundations, drainage inlets, manholes, and anywhere differential movement between the pavement and a structure (or another existing pavement) may take place they are typically filled with a joint filler material to prevent water and dirt infiltration.

Isolation Joints in rigid pavement

•

CONSTRUCTION JOINTS:-

It is a joint between slabs that results when concrete is placed at different times. This type of joint can be further broken down into transverse and longitudinal construction joints longitudinal construction joints also allow slab warping without appreciable separation or cracking of the slabs.


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4. TEST ON AGGREGATE AND BITUMEN

I. CALIFORNIA BEARING RATIO TEST (CBR TEST) •

STANDARD:IS: 2720(part 16) 1979.

•

DEFINITION:California bearing ratio is the ratio of force per unit area required to penetrate in to a soil mass with the circular plunger of 50 mm diameter at the rate of 1.25 mm per minute.

•

APPARATUS:        

•    

Mould 2250 cc capacity with base plate, stay rod and wing nut, confirming to 4.1, 4.3 and 4.4 of IS: 9669-1980. coller confirming to 4.2 of IS: 9669- 1980. Spacer disc confirming to 4.4 of IS: 9669- 1980. Metal rammer confirming to IS: 9189- 1979. Expansion measuring apparatus with the adjustable steam, perforated plate, tripod confirming and to weight confirming to 4.4 of IS: 9669- 1980. loading machine having a capacity of at least 5000 KG and equipped with a movable head of the base that travel at uniform rate of 1.25 mm per minute for use in forcing the penetration plunger into the specimen. Dial gauge two number reading to 0.01mm. IS Sieves 37.50 or 22.50 or 19mm and 4.75mm. Miscellaneous apparatus such as mixing bowl, a straight edge, scale, soaking tank, drying oven, filter paper, dishes and deliberated measuring jar.

PROCEDURE:There are two type of methods in compacting soil specimen in the CBR moulds. Static compaction method. Dynamic compaction method. The material used in the above two method shall pass 19mm sieve for fine grained soil and 37.50mm sieve for coarse material up to 37.50mm.


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 Replace the material retained on 19mm sieve by an equal amount of material passing 19mm sieve and retained on 4.75mm sieve.  Replace the material retained on 37.50mm sieve by an equal amount of material passing 37.50mm sieve and retained on 4.75mm sieve.

•

STATIC COMPACTION:In this method calculate the mass of wet soil at required moisture content to give a desired density when compacted in a standard test mould as given below. Volume of mould = 2250 cc. Weight of dry soil (W) = 2250× MDD Weight of wet soil = 1+------× W 100 Weight of water = weight of wet soil - weight of dry soil. Where M = optimum moisture content obtained from the laboratory compaction test.  Take oven dried soil Sample of calculated weight and thoroughly mixed with water (O MC) as obtained from the above equation.  Record the empty weight of the mould with base plate, with extension coller moved (M1).  Place the correct mass of the wet soil into the mould in five layer.  Gently compact each layer with the spacer disc.  Compact the mould by pressing it in between the plates of the compression testing machine until the top of spacer disc comes flush with the top of the mould.


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 Held the Load for about 32 seconds and then release.  In some soil type where a certain amount of rebound occurred, it may be necessary to reapply load to force the spacer disc slightly below the top of the mould so that on rebound the right volume is obtained.  Remove the mould from the compression testing machine.  Remove the spacer disc and weight the mould with compacted soil (M2).  Replace the extension Collar of the mould.  Prepare two more specimens in the same procedure as described above.

CBR TEST READING S.NO.

DIAL GAUGE READING(mm)

PROVING RING READING

1

0.50

0

2

1.00

0.3

3

1.50

0.8

4

2.00

1.2

5

2.50

1.7

6

3.00

2.2

7

50

3.5

8

0

5.1

9

50

6.9

10

0

8.6

11

50

10

12

0

108

13

50

11.2

14

0

11.6

15

50

12

16

0

12.4

17

50

12.8

18

0

13.4

19

50

14

20

0

14.7

21

50

15.2

22

0

16

23

50

16.4

24

0

17.2

25

50

18


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•

DYNAMIC COMPACTION:-



Take a representative sample of weighing approximately 6 KG and mix thoroughly at OMC. Record the empty weight of mould with this plate, with extension Collar removed (m1). Replace the extension Collar of mould. Insert the spacer disc over the base plate and place of coarse filter paper on the top of the spacer disc. Place the mould on a solid base such as a concrete floor of plinth and compact the wet soil into the mould in five layers of approximately equal mass each layer being given 56 below with 4.90 KG hammer equally distributed and dropped from a height of 450 MM above the soil. The amount of soil used shall be sufficient to fill the mould, leaving not more than about 6 MM to be a struck off when the extension Collar is removed. Remove the extension Collar and carefully level the compact soil to the top of mould by means of a straight edge. Remove the spacer disc by inverting the mould and weigh the mould with compact soil (m2). Place of filter paper between the base plate and inverted mould. Replace the extension Collar of the mould. Prepared two more specimen in the same procedure as described above. In both the cases of compacts, if the sample is to be socked, take a representative sample of the material at the beginning of compaction for determination of moisture content. Each Sample shall weigh not less than 100 g for fine grained soil and not less than 500 Place the adjustable stem and perforated plate on the compacted soil specimen in the mould. Place the weights to procedure a surcharge equal to the weight of base material and pavement to the nearest 2.5 KG on the perforated plate. Immerse the whole mould and weights in a tank of water allowing free access of water to the top and bottom of a specimen for 96 hours.

   

          


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CBR Test Apparatus

•

TEST FOR SWELLING:-

       

Determine the initial height of specimen (h) in mm. Mount the expansion-measuring device along with the tripod on the edge of The mould and record the initial dial gauge reading (ds). Keep this set up as such undisturbed for 96 hours noting down the readings Every day against the time of reading. This test is optional and may be omitted if not necessary. Maintain a constant water level throughout the period of soaking. Note the final reading of the dial gauge at the end of soaking period (dh).

•

CALCULATIONS FOR SWELLING

df-ds Expansion ratio = ----------- x 100 H ds= Initial dial gauge reading in mm df= final dial gauge reading in mm h = initial height of specimen in mm


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•

PENETRATION TEST  

•

After 96 hour of soaking take out the specimen from the water and remove the extension Collar, perforated disc, surcharge weight and filter paper. Drain off excess water by placing the mould inclined for about 15 minutes and weigh the mould.

TESTING OF CBR SPECIMEN:         

Place the mould on lower plate of testing machine with top face exposed to prevent upheaval of soil in to the whole of surcharge weights, place 2.5 KG. Annular weights on the soil surface prior to seating that penetration plunger after which place the reminder of the surcharge weights. Set the plunger under a load of 40 KG so that full contact is stabilised between the surface of a specimen and the plunger. Set the stress and strain gauges to zero. Consider the initial load applied to the plunger as the zero load. Applied the load at the rate of 1.25mm/min. Take the reading of the Load at penetration of zero, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 4, 5, 7.5, 10 and 12.5. Raise the plunger and detach the mould from the loading equipment. Collect a sample of about 20 to 50 gms of soil from the top 30 MM layer of a specimen and determine the water content in accordance with IS: 2720 ( part 4 ) 1973. Examine the specimen carefully after the test is completed for the presence of any oversized soil particle, which are likely to affect the result if they happen to be located directly below the penetration plunger.


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•

CALCULATION OF CBR FROM LOAD PENETRATION CURVE:    

Plot the load penetration curve in natural a scale, load on Y-axis and If the curve is uniformly convex upwards although the initial portion of the curve may be concave upwards due to surface irregularities may correction by drawing a tangent to the upper curve at the point of contra flexure as below. Take the intersection point of tangent and the X axis as an origin. Calculate the CBR value for penetration of 2.50 MM and 5.00 MM. Corresponding to the penetration value at which CBR is to be desired, take the corrected load value from the load penetration curve and calculate the CBR from the equation,

CBR= load carries by specimen X100 Load carries by standard specimen

Where PT - corrected unit test load corresponding to chosen penetration from Load penetration curve. PS - total a standard load for the same depth of penetration, which can be taken from the table below. CF - proving a ring correction factor.


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Standard load curve at a specified penetration.

penetration depth (mm)

Unit standard load kgf/cm2

Total standard load (kgf)

2.50

70

1370

5.00

105

2055

7.50

134

2630

10.00

162

3180

12.50

183

3600


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•

REPORT:-

     

Repeat the CBR value to the nearest second decimal. Take the average of three test a specimen as the CBR value of the test. Generally, the CBR value at 2.50 MM penetration will be greater than that at 5.00 MM penetration and in such case take the value at 2.50 MM as the CBR value. If the CBR value corresponding to a penetration of 5.00 MM exceed that of 2.50 MM, repeat the test. If the identical result follow, take the value corresponding to 5.00 MM as the CBR value.

•

PRECAUTIONS:-

 

Clean the holes of base plate and that of perforated disc thoroughly. Aligns the surcharge weight with the plunger so that the plunger penetrate freely into the soil.

II. •

IMPACT TEST INTRODUCTION:Toughness is the property of material to resist impact due to traffic load, the road stone are subjected to the pounding action and impact and there is possibility of stone breaking into a smaller pieces. The road stone should therefore be tough enough to resist fracture under the impact’s test designed to evaluate the toughness of the stones i.e., the resistance of fracture under repeated impact may be called an impact test for road stones.

•

OBJECT: To determine the toughness of road stone material by impact test.


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•

APPARATUS:-

a) Impact testing machine. b) Measure: a cylindrical metal measure having internal diameter 75 MM and depth 50 MM for measuring aggregate. c) Tamping rod: a straight metal tamping rod of circular cross-section, 10 MM in diameter and 230 MM long, rounded at one end. d) Sieve: IS sieve of size 12.5 MM, 10 MM, and 2.36 MM for sieving the aggregate. e) Balance: a balance of capacity not less than 500 GM to weigh accurate up to 0.1 gm. f) Oven: a thermostatically controlled drying oven capable of maintaining constant temperature between 100°C to 110°C.

Impact Test Machine •

PROCEDURE:-

The test sample consist of aggregates passing through 12.5 MM sieve and retained on 10 MM sieve and dried in an oven for four hour at the temperature of 100°C to 110°C and cooled. Test aggregate are filled up to about one third full in the St cylindrical measure and tamped 25 times with the rounded of the tamping rod. Further quality of aggregate is then added up to 2/3 full in the cylinder and 25 stocks of tamping rod are given. The measure is now filled with the aggregate to overflow, tamped 25 times. The surplus aggregate are struck off using the tamping rod as a straight edge. The net weight of aggregate in the measure is determined to the nearest gram and this weight of aggregate is used for carrying out duplicate test on the same material. The impact machine is placed with its bottom plate flat on the floor so that the hammer guide columns and vertical. The cup is fixed firmly in position on the base of the machine and the whole of the test sample from the cylindrical measure is transferred to the cup and compacted by tamping with 25 strokes. The hammer is raised until its lower face is 380 MM above the upper surface of the aggregate in the cup, and allow it to fall freely on the aggregate. The test sample is subjected to a total 15 blows, each being delivered at an interval of not less than one second. The crusted aggregate is


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then removed from the cup and the whole of it sieved on the 2.36 MM sieve until no further significant amount passes. The fraction passing the sieve is weighed accurate to 1.0 gm. The fraction retained on the sieve is added it should not be less the original weight of the specimen by more than 1 g, if the total weight is less than the original by over 1 g the results should be discarded and fresh test made.

•

CALCULATIOS:-

The aggregate impact value is expressed as percentage the fine formed in term of the total weight of the sample. Weight of aggregate sample in the cylindrical measure, W1 = 325 gm. Weight of crushed aggregate after passing through 2.36 mm sieve W2 = 70 gm. Aggregate impact value = W2/W1 ×100 =70/325 ×100 = 21.53 % Where, W1 = original weight of sample. W2 = weight of fraction passing 2.36 MM IS sieve.

•

RESULTS:The impact value of aggregate obtained in test reported = 21.53%

•

LIMITS:Impact value

Surface strength

less than 10%

exceptionally strong

10 to 20%

as strong

20 to 30%

satisfactory for road surfacing

greater than 35%

weak road surfacing


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III. •

CRUSHING STRENGTH TEST INTRODUCTION:-

The principal mechanical property in the road stones are Q satisfactory resistance to crushing under the roller during construction and adequate resistance to surface of abrasion under traffic. also surface a stress under rigid tyre rims of havlely loaded animal, drawn vehicle are high enough to consider the crushing strength of road stones may be determined either on aggregates are all cylindrical is specimen cut out of rocks. These two test are quite different in not only the approach but also in the expression of I results. Aggregate used in road construction, should be a strong enough to resist crushing under traffic wheel thought load if aggregates are weak, the stability of the pavement structure is likely to be adversely affected.


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The strengths of coarse aggregate is assessed by aggregate crushing test. The aggregate crushing value provider. A relative measure of resistance to crushing under a gradually applied compressive load.to achieve a high quality of pavement, aggregate possessing low aggregate crushing value should be preferred.

•

APPARATUS:-

The apparatus for the standard aggregate crushing test consist of following: 1) Steel cylindrical with open ends, and internal diameter 25.2 cm, a square base plate plunger having a piston of diameter - with a hole provided across the stem of the plunger. A rod could be inserted for lifting or placing the plunger in the cylinder. 2) Cylindrical measure having internal diameter of 0.5 cm and height 18 cm. 3) Steel temping load with one rounded end, having a diameter of 1 cm and length 45 to 60 cm. 4) Balance of capacity - KG with accuracy up to 1 g. 5) Compression testing machine capable of applying load of 40 tons, at uniform rate of loading of four tons per minute.

•

PROCEDURE:-



The aggregate passing 12.5mm IS sieve and retained on 10 MM IS sieve selected for a standard test. The aggregate should be in surface dry condition before testing. The aggregate may be dried by heating a temperature 100̊ C to 110°C for a period of four hour and is tested after being cooled to room temperature. The cylindrical measure is filled by the test sample of aggregate in three layers of approximately equal depth each layer being tamped 25 times by the rounded end of the tamping rod. After the third layer is tamped .the aggregate at the top of the cylindrical measure is a level off by using the tamping rod as a straight edge. About of aggregate is required for preparing two test samples. The test sample thus taken is then weighed. The amount weight of sample is taken in the repeat test.

 


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

 

•

The cylinder of the test apparatus is placed in position on the base plate; one Thired of the test sample is placed in the cylinder and tamped 25 times by the tamping rod. Similarly, the other two part of the test specimen are added, each layer being subjected to 25 blows. The total depth of the matter is; in the cylinder after attempting shall however be… The surface of the aggregate is labelled and the plunger inserted so that it rests on this surface in the level position. This cylinder with the test Sample and plunger in the position is placed on compression testing machine. Load is then applied through the plunger at the uniform rate of 4 tons per minute until the total load is 40 tons and then the load is released. Aggregate including the crushed portion are removed from the cylinder and sieved on a 2.36 MM IS sieve. The material which passes this sieves is collected. The above crushing test is repeated on second sample of the same weight in accordance with above test.

CALCULATIONS:-

Weight of empty cylinder W1 = 1981 gm. Weight of full cylinder W2 = 4745 gm. Weight of aggregate = WA = W2 – W1 = 4745 – 1981 gm. = 2764 gm. Weight of aggregate passed from sieve 2.36 mm = Wb = 608 gm. Crushing value of aggregate = Wb/Wa ×100 = 608/2764 ×100


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= 22%

•

RESULTS:-

The crushing value of aggregate obtained in test reported = 22%

IV.

PENETRATION TEST:

•

INTRODUCTION:The consistency of bituminous materials varies depending upon several factors such as constituents, temperature etc. The penetration test determines the consistency of these materials for the purpose of grading them, by measuring its depth to which standard needle is penetrate under specific condition of standard load, duration and temperature. Thus the basic principal of the penetration test is the measurement of the penetration of a standard needle in a bitumen sample maintained at 25c during five seconds, the total weight of the needle assembly being 100g.


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•

OBJECTIVE:To determine the penetration value of a given sample.

•

APPARATUS:-

The apparatus for conducting penetration test on bitumen consist of penetrometer, Container, Thermometer, controlled water bath, stop watch and transfer dish.

Standard Penetrometer

•

PROCEDURE:    

The bitumen is heated to a pouring consistency, about 75̊C to 100̊C. above the temperature at which bitumen softens. The sample material is thoroughly stirred to make it homogeneous and free from air bubbles and water. The sample is then poured into the containers of 35mm depth. The sample is then placed on transfer tray and cooled in atmosphere at temperature between 15-30̊c for 60-90 minutes. The sample is then placed in controlled water bath at a temperature of 25̊c for a period of 60-90 minutes.


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    

•

•

The sample is then placed under the needle of the penetrometer. Now the tip of needle is made to just touch the top surface of the bitumen sample. The initial reading of penetrometer is adjusted to zero and then the needle is released exactly for a period of 5 seconds by pressing the knob and final reading is taken on dial. The needle assembly is then raised and the penetration needle is removed and replaced by clean, dry needle. The test is repeated on the sample in the other container, after keeping in the water bath maintained at a temperature of 25̊c.

OBSERVATION TABLE:Penetrometer Dial Reading

TEST-1

TEST-2

TEST-3

Initial

155

240

290

Final

260

295

345

Penetration Value

10.5

5.5

5.5

RESULTS:The difference between the initial and final penetration readings is taken as the penetration value.

V.

•

LOS ANGELES ABRASION TEST OF THE AGGREGATE

INTRODUCTION:-

The principal of Los Angeles abrasion test is to find the percentage wear due to relative rubbing action aggregate and steel ball used as abrasive charge the pounding action of these balls also exists while conducting the test some investigator believes that this test to be more dependable on rubbing and pounding action simulate the filled condition where both abrasion and impact occur. Los Angeles abrasion test has been standardised by the ASTM, AAHO and also by the


Page | 34

ISI. A standard specification of Los Angeles abrasion value is also available for various type of pavement construction. •

APPARATUS:-

The apparatus consist of hollow steel cylinder, enclose at both ends having are inside diameter 70 cm and inside length of 50 cm maintained and stuff about which it rotate on a horizontal axis. An opening is provided in such a way that when closed and fixed bolt and nut. It is dusttight and the interior surface is preferably cylindrical. A removable steel shelf projecting radially 8- 8 cm into the cylinder into the cylinder rigidly parallel to the axis. The self is fixed at a distance of 125 cm from the opening measured along the circumference in the direction of rotation. Abrasive charge consisting of cast iron sphere approximately 4.8 cm in the diameter and 390 to 445 g in weight are used. The weight of sphere used as the abrasive charge and the number of sphere to be used are a specified depending upon the grading of the aggregate tested. The aggregate grading has been standardised as a, B, C, D, E, F, and G for this test and the IS a specification for the grading and the abrasive charge to be used are in the given table IS sieve with 1.70 MM opening is used for separating the finer after the abrasion test.

Los Angeles abrasion resistance •

PROCEDURE:Clean aggregate dried in an oven at 105°C to 110°C to constant weight. Confirming to anyone of the grading as to go as per table is used for the test. The grading or gradation used in the test should be nearest to the grading to be used in the construction. Aggregate weighing five KG for grading a, B, C, D and 10 KG for grading E, F, or G may be taken as test a specimen and placed in the cylinder. The abrasive charge is also chosen in accordance with the table. Depending upon the grading of the aggregate and placed in the cylinder of machine. The cover is then fixed in dust tight. The machine is rotated of speed of 32 t 33 roll per minute. The machine rotated Fe 500 revolution for grading a, B, C, and d and for grading E, F, and G


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it shall rotated Fe 1000 revolution. The machine should be balanced and delivering in such a way as to maintain uniform speed After the desired number of revolution the machine is stopped and the material is discharge from the machine taking care to take net entire stone dust. Using the sieve of size larger than 1.70 MM IS sieve the material is first separated into the two part, and the finer portion take net and see further on A 1.7 MM IS sieve. The portion of material coarser than 1.7 MM size washed and dried in an oven at 105°C to 110°C to constant weight and weighed correct to 1 g.

•

CALCULATION:The difference between the original and final weight of Sample expressed as a percentage of original weight of the sample is reported as the percentage wear.

•

Sample number

Weight

Total weight of dry Sample(w1) grams

5000 g

Weight of aggregate retained on 1.7 MM IS sieve after the test (w2) grams

3935 g

Loss in weight due to be (W1-w2) gram

1065 g

Los Angeles abrasion value (w1-w2/w1 ×100)

10.65/5000 ×100 = 21.3%

RESULT:The result of the Los Angeles abrasion test is expressed as percentage WEAR and the average value of two test may be adopted as the Los Angeles abrasion value. The abrasion value of given aggregate sample is 21.3%

VI.

•

FLASH & FIRE POINT OF BITUMEN

INTRODUCTION:-

The flash and fire point of bitumen grade 30-40. • APPARATUS:Pensky-Marten Closed Tester, Thermometer.


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Pensky-marten closed tester

•

THEORY:-

Bituminous material leave out volatiles at high temperatures depending upon their grade. These volatile vapours catch fire causing a flash. The flash point is the lowest temperature at which flash occurs due to ignition of volatile vapours when a small flame is brought in contact with the vapours of a bituminous product, gradually heated under standardised condition. When bituminous material is further heated to a higher temperature, the material itself catches and continues to burn; the lowest temperature causing this is the fire point. Fire point is always higher than flash point. The flash point of a material is the lowest temperature at which vapour of a substance momentarily take fire in the form of flash. The fire point is the lowest temperature at which the material gets ignited and burns under specific conditions of test.


Page | 37

•

PROCEDURE:-

All parts of cup are cleaned and dried thoroughly. Material is filled into cup upto filling mark. Lid is placed to close the cup in a closed system. All accessories including thermometer of specified range are suitably fixed. Bitumen sample is then heated. Stirring is done at regular intervals. The test flame is lit and applied at intervals depending upon expected flash and fire point. First application is made at about 17°C below actual flash point and then at every 1°C. Stirring is discontinued during the application of the test flame.

•

RESULT:-

Flash point of bitumen = 176°C Fire point of bitumen =180°C •

RECOMMENDED VALUES:-

The minimum value of flash point by Pensky Martens closed type apparatus is 175°C for all grades of bitumen.

VII.

SOFTENING POINT OF BITUMEN/ TAR.


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•

INTRODUCTION:The Softening Point of bitumen or tar is the temperature at which the

substance attains particular degree of softening. As per IS: 334-1982, it is the temperature in ºC at which a standard ball passes through a sample of bitumen in a mould and falls through a height of 2.5 cm, when heated under water or glycerine at specified conditions of test. The binder should have sufficient fluidity before its applications in road uses. The determination of softening point helps to know the temperature up to which a bituminous binder should be heated for various road use applications. Softening point is determined by ring and ball apparatus. •

APPARATUS:-

(i) The ring and ball apparatus consisting of (a) Steel balls-two numbers each of 9.5 mm diameter weighing 3.5 ± 0.05 g.

(b) Brass rings-two numbers each having depth of 6.4 mm. The inside diameter at bottom and top is 15.9mm and 17.5 mm respectively. (c) Ball guides to guide the movement of steel balls centrally. (d) Support -that can hold rings in position and also allows for suspension of a thermometer. The distance between the bottom of the rings and the top surface of the bottom plate of the support is 25mm.

(i) Thermometer that can read up to 100° C with an accuracy of 0.2° C.


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(ii) Bath–heat resistant glass beaker not less than 85 mm in diameter &1220mm deep. (iii) Stirrer •

PROCEDURE:-

(i) Preparation of test sample: Heat the material to a temperature between 75-100° C above its softening point; stir until, it is completely fluid and free from air bubbles and water. If necessary, filter it through IS sieve 30. Place the rings previously heated to a temperature approximating to that of the molten material, on a metal plate which has been coated with a mixture of equal parts of glycerine and dextrin. After cooling for 30 minutes in air, level the material in the ring by removing the excess material with a warmed, sharp knife. (ii) Assemble the apparatus with the rings; thermometer and ball guides in position (iii) Fill the bath with distilled water to a height of 50mm above the upper surface of the rings. The starting temperature should be 5° C. Note: Use glycerine in place of water if the softening point is expected to be above 80° C; the starting temperature may be kept 35° C. (iv) Apply heat to the bath and stir the liquid so that the temperature rises at a uniform rate of 5 ± 0.5 °C per minute. (v) As the temperature increases the bituminous material softens and the balls sink through the rings carrying a portion of the material with it. (vi) Note the temperature when any of the steel balls with bituminous coating touches the bottom plate. (vii) Record the temperature when the second ball touches the bottom plate. The average of the two readings to the nearest 0.5°C is reported as softening point.

•

PRECAUTIONS:-


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(i) Distilled water should be used as the heating medium. (ii) During the conduct of test the apparatus should not be subjected to vibrations. (iii)The bulb Temperature when the ball touches bottom, °C

1

46.4 °C of the thermometer should be at about the same level as the rings. •

OBSERVATIONS:-

•

RESULT:-

2 45.8 °C

Softening point of bitumen / tar = 46.4+45.8 /2 =46.1 °C.


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5. COMPARISON BETWEEN FLEXIBLE AND RIGID PAVEMENT

PROPERTIES

FLEXIBLE

DESIGN PRINCIPLE

NORMAL LOADING

Empirical method based on Designed and analysed by load distribution using the elastic theory characteristics of the complements Granular material Made of cement concrete either plan, reinforced or prestressed concrete Low of negligible flexible Associated with rigidity or strength flexural strength or slab action so the load is distributed over a wide area of subgrade soil Elastic deformation Acts as beam or cantilever

EXCESSIVE LOADING

Local depression

Causes cracks

STRESS

Transmits vertical and compressive stresses to the lower layer Constructed in number of layers No stress is produced

tensile stress temperature increases

MATERIAL

FLEXURAL STRENGTH

DESIGN PRACTICE THE TEMPERATURE

REGID

and

Laid in slabs with steel reinforcement Stress is produced

FORCE OF FRICTION

Less deformation in the sub- Friction force is high grade is not transferred to the upper layers OPENING TO TRAFFIC Road can be used for traffic Load cannot be used until 14 within 24 hour day of curing SURFACING Rolling of surfacing is Rolling of surfacing is not needed needed Difference between flexible and rigid pavement

6. ROLE OF STABILISATION

Pavement materials include a combination of coarse and fine aggregate with a proportion of a smaller clay/silt -sized particles. The objective is to ensure a final grading matrix that will allow maximum compaction of the product with the least void present. This is to achieve a solid layer that is in part impervious to water infiltration. Pavement materials can be used in different layers of the pavement and requirement of such a layers will be determined by applied load and payment compaction selected by designer.


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For the pavement containing mechan1ically stabilised materials and/or modified materials, the limiting design criteria is the vertical strain at the top of the subgrade. For a stabilised and higher binder content materials, the vertical strain at the top of subgrade is not only design criteria as the fatigue life of cemented material must also be considered. The fatigue life of cemented material is usually the governing criterion.

High-performance quarried materials will likely be obtained from the nearest possible source in order to minimise transport costs. Often, however, imported material may not be sufficiently strong payment design requirements. in such cases, the solution is found in the design of either stronger payment layers or a reduction in the stresses requirement for the layer.one of the most cost effective ways to make the pavement stronger is to modify or a stabilised the pavement material.as an alternative, it is possible to reduce the stress requirement by the stiffening for foundation. Again, this can be done by either modifying are stabilising the foundation

•

LIME STABILISATION

Lime stabilisation or modification is used in the road construction to improve the quality of existing material within the construction project. Lime is an effective addictive for plastic soil, improving both workability and a strength. Lime stabilisation can be used to:    

•

modify marginal material to bring it within specification or for performance requirement increases strength as an alternative to cementetious stabilisation enhance volumetric stability for various layers of select material improve surface stability of unsealed road

CEMENTITIOUS STABILISATION

When stabilising the cement, the working time of the resultant material can be critical. The time available to deliver, incorporate and compact a pavement layer needs to be understood before project commencement. With cement as the only binder, the time for performing placement and compaction process is limited to approximately two-hour from the incorporate of the cement into the moistened payment materials. No rework time is normal provided for. This can be create a demanding schedule with little opportunity for error management on the site. Cement as the only binder is not often used due to working time restrictions. In addition, higher shrinkage rates can result in an increased cracking tendency. Addition of FA to the binder extends the working life of the stabilised material, allows more time placement in compaction of the material and mitigates risks typically associated with a single cement binder.


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7. DESIGN AND COST ANALYSIS OF FLEXIBLE AND RIGID PAVEMENT The structural capacity of flexible payment is attended by combined action of the different layer of the payment. The load is directly applied on the wearing course and it gets dispread with the depth in base, sub base and subgrade layers and then ultimately to the ground. Since stress induced by traffic load is highest at the top, the quality of top and upper layer of material is better. The subgrade layer is responsible for transferring the load from above layers to the


Page | 44

ground. Flexible payments are design in such a way that the load transmitted to the subgrade does not exceed its bearing capacity. Consequently, the thickness of the layer would vary with CBR of soil and it would affect the cost of pavement.

The thickness design of flexible payment also varies with the amount of traffic. The range of variation in volume at a different highways has direct effect on the repetitions of traffic loads. The damaging effect of different axle loads is also different. The Indian Road Congress method of flexible pavement design uses the concept of ESAL for the purpose of flexible pavement design and the same has been used in this study also.

 DESIGN OF FLEXIBLE PAVEMENT BY GROUP INDEX METHOD in order to classify the fine grained soil within one group and for judging their suitability as subgrade material, and indexing system has been introduced in HRB classification which is term it as group index. Group index is the function of percentage materials passing through 200 Mesh sieve (0.074 mm), liquid limit and plasticity index of soil and is given by equation: (0.074 mm). Liquid limit and plasticity index of soil is given by equation: G.I = 0.2a + 0.005ac + 0.01bd Here, a = that portion of material passing through0.074 mm sieve, greater than 35 and not exceeding 75%. b = that portion of material passing through 0.074 mm sieve, greater than 15 and not exceeding 35%. c = that value of liquid limit in excess of 40 and less than 60 d = that value of plasticity index exceeding 10 and not more than 30 Or, GI = (F-35)0.2 + 0.05(WL-40) + 0.01(F-15) (IP-10) DATA: F = 66% WL = 55% IP = 31% GI = (F-35)0.2 + 0.05(WL-40) + 0.01(F-15) (IP-10) = 17.35 So pavement thickness = 700mm Thickness of surface course = 35mm Thickness of DBM = 145mm Thickness of base course = 200mm Thickness of sub base = 320mm


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 CALIFORNIA RESISTANCE VALUE METHOD

F.M Hakeem and R.M.carmany in 1948 provided design method based on stabilometer R-value and Cohesimeter computer value. Based on performance data it was estabilised by Hveem and Car many that payments thickness varies directly with R value and logarithm of load repetitions. It varies inversely with fifth root of computer value. The expression for pavement thickness is given by the empirical equation. T = K (TI) (90-R)/C1/5 Here K = total thickness of pavement in centimetre. TI = numerical constant = 0.166. R = stabilometer resistance value. C = Cohesiometer value The annual value of the equivalent wheel load (EWL) here is the accumulated some of the products of constant and the number of axle loads. The various constant for the different number of the axles in group are given below:-

Number of axles

EWL constant (yearly basis)

2

330

3

1070

4

2460

5

4620

6

3040

DATA K = 0.166, TI = 9.66, R = 44, C = 61 Pavement thickness is given by the empirical equation:T = K (TI) (90-R)/C1/5 CALCULATION TI = 1.35(EWL) 0.11


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TI = 1.35(32729750)0.11 TI = 9.66 T = K (TI) (90-RC)/C1/5 T = 0.166(9.66) (90-44)611/5 T = 730 mm So pavement thickness = 730 mm Thickness of surface course = 35 mm Thickness of DBM = 145 mm Thickness of base course = 210 mm Thickness of sub base = 340 mm

 DESIGN OF FLEXIBLE PAVEMENT BY CBR DATA

               

Length of road = 3.45 km Traffic intensity as worked out = 1001 cv/d average Growth rate of traffic (assumed) = 7.5 % Total period of construction = 4 months Design C.B.R of sub grade soil = 5.00 % Design period of the road = 10 years Initial traffic in the year of completion of construction A = P×(1+r)×r A = traffic in the year of completion of construction P = traffic at last count April 2013 r = annual growth rate of traffic x = number of years between the last census and the year of completion of construction A =1001x(1 + 0.075)x 11076 CV/day Vehicle damage factor = 3.5 ; standard axle per CV (as per Clause 3.3.4.4 table 1 of IRC -37-2001) design calculation Initial traffic in design lane = initial traffic x distribution factor = 1076 x 0.75 = 807.05 CVPDN = [365 x {(1+r)x-1}xAxF]/r = 365x[{(807(1+0.075)^101 }x3.5]/0.075 = 14.58 msa or say 15.00 msa Total pavement thickness for design C.B.R = 660 MM


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  

(As per plate – 2 of IRC -37-2001) the thickness of the individual component layer of flexible pavement by CBR method is given below: so pavement thickness = 660 mm thickness of the surface course = 40 mm thickness of DBM = 70 mm thickness of base course = 250 mm thickness of sub base = 300 mm

CONCLUSION

From this report on payment it is observed that flexible payment are the most economical for lesser of volume of traffic. The life of flexible payment is near about 15 years whose initial cost is low needs a periodic maintenance after a certain period and maintenance costs are high. The


Page | 48

life of rigid payment is much more than flexible pavement of about 40 years approx. 2.5 times life of flexible payment whose initial cost is much more than flexible payment but maintenance cost is very less.

The pavement is designed as flexible pavement upon a black cotton soil subgrade, the CBR method as per IRC 37-2001 is most appropriate method than other methods.

The pavement is designed as a flexible method from which each method is design on the basis of their design thickness from which each method has different cost analysis of a section, from which CBR as per IRC is most appropriate in term of cost analysis.

The pavement is designed as a rigid pavement, the method suggested by IRC is more suitable.

BIBLIOGRAPHY


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     

AASHTO 1993, “AASHTO guide for design of pavement structure” American Association of State Highway and transportation officials passing Washington, D.C. IRC: 37-2001 “code of guideline for design of flexible pavement”, Indian Road Congress, New Delhi 2001. IRC: 58-2002 “code of guideline for design of plain jointed rigid payment for Highway”, Indian Road Congress, New Delhi 2002. Khanna, S.K. justo, C.E.G, (1993) “highway engineering” new Chand and bros, seventh edition, New Delhi Prasad, bageshwar (2007) “life-cycle cost analysis of cement concrete road VS bituminous road” Indian Highway, Vol.35, No.9.


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project report on pavement design

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