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November 1, COMPARATIVE STUDY BETWEEN FLEXIBLE AND RIGID PAVEMENT FOR STABILIZED AND

2014 UNSTABILIZED SOIL

A MINOR PROJECT

ON

COMPARATIVE STUDY BETWEEN FLEXIBLE AND RIGID PAVEMENT

FORSTABILIZED AND UNSTABILIZED SOIL

Submi tted to

SANGHAVI INSTITUTE OF MANAGEMENT & SCIENCE,INDORE

Institute of Technology and Management

Rajiv Gandhi ProudyogikivVishwavidhyalayaBhopal (M.P.)

2014-2015

In The Partial fulfillment of Bachelor Degree in Civil Engineering

Guided by: Submitted to: Submitted by:

Er. Yogesh Sharma H O D CIVIL ParmanandPatidar

BE VII Sem( Civil)Roll No: 0837CE111070

RAJIV GANDHI PROUDYOGIKI VISHWAVIDHYALAYA,BHOPAL, (MP)

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SIMS,INDORE (2011-2015)

CERTIFICATE

This is to certify that the minor project entitled, COMPARATIVE STUDY

BETWEEN FLEXIBLE AND RIGID PAVEMENT FOR STABILIZED AND

UNSTABILIZED SOIL Submitted by Mr.ParmanandPatidarinpartial

fulfillment of the requirements for the award of bachelor of engineering degree in

civil engineering under the subject minor civil engineering project at the

RAJIV GANDHI PROUDYOGIKI VISHWAVIDYALAYA, BHOPAL.

The work has been examined by us and recommended for acceptance.

EXTERNAL EXAMINER INTERNAL EXAMINER

DATE: DATE:


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ACKNOWLEDGMENT

It is always a pleasure to remind the fine people in the Engineering Work u come

to know for their sincere guidance I received to uphold my practical as well as

theoretical skills in engineering.

Mostly we would like to thank ER. Yogesh Sharma (Guide) for extending their

friendship towards us and making a pleasure-working environment on the field and

lab. A paper is not enough for me to express the support and guidance we received

from them almost for all the work we did there. They were a great help not only on

how work take place on field but also told some life learning experience they were

blessed with.

Secondly we would like to thank Prof. R P Pandey (HOD of Civil Engineering ) for

giving opportunity for doing minor project.

Thirdly we would like to thank ER. PushpendraSoni (Minor project co-ordinator)

for the positive attitude he showed for our work, always allowing us to question

him and giving prompt replies for our uncertainties in all the fields including

educational, and managerial to practical work.

Finally we apologize all other unnamed who helped us in various ways to have a

good project.

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ABSTRACT

India is an emerging economy and second faster growing country of the world and

a developing country, Infrastructure is a key factor in the growth of each country,

Infect it is a indicator that indicate how much a country is growing and at which

rate.

Transportation and road network is a major sector in the infrastructure. India

a huge agricultural land and 65% of the population of country lives in rural areas,

therefore it is very necessary to connect rural and urban areas for the socio

economic growth of country.

The village is only connected with fair weather road. If the said villages are

connected with BT road by the approach road, the villages around the way will be

economically benefited. The Villagers are mainly dependent on the agriculture and

for proper transport and getting proper price of their produces, all weather road is

necessary, A part from this, villagers will also get the facilities of good education

and health. Therefore, to ensure socio-economic transforming breaking the

isolation of village communities, elimination of disparity between rural and urban

population and bringing about urban rural integration.

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November 1, COMPARATIVE STUDY BETWEEN FLEXIBLE AND RIGID PAVEMENT FOR STABILIZED AND2014 UNSTABILIZED SOIL

CONTENT

Page No.

CHAPTER-1 INTRODUCTION 9

1.1General 9

1.2Pavement 10

1.3Purpose Of Pavement 11

1.4Selection Of Type Of Pavement 12

1.5Selection Criteria 13

1.6Factors For Comparing Flexible & Rigid Pavement 14-50

1.7Considerations for Flexible vs. Rigid Pavements 51

1.8 Soil Stabilization 52-53

CHAPTER-2 EXPERIMENTAL PROGRAMME 54

2.1Properties Of Soil 55-56

2.2Particle Size Distribution (sieve analysis) 56-58

2.3CBR Test 59-60

CHAPTER-3 RESULTS 61-66

CHAPTER-4 CONCLUSION 67-68

REFERENCE 69

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LIST OF FIGURES

Fig. 1 Typical Cross Section Of Flexible Pavement 14

Fig. 2 . Layers Of Flexible Pavement 17

Fig. 3 Typical Rigid Pavement 18Fig. 4 Layers Of Rigid Pavement 19

Fig. 5 PCC Surface 20

Fig. 6 Rigid Pavement Slab 21

Fig. 7 Rigid Pavement Showing Contraction Joints 23

Fig. 8 Skewed Contraction Joint 24

Fig. 9 Construction Joint 25

Fig.10 Longitudinal and Transverse Construction Joints 26

Fig.11 Stainless Steel-Clad Dowel Bars 27

Fig.12 Dowel Bars in Place at a Construction Joint 27

Fig.13 CBR Curve For Flexible pavement Design 29

Fig14 Thickness of crust required for different traffic 31

Fig15 Thickness of crust required for different traffic 32

Fig.16 Thickness of crust required for different traffic 34

Fig.17 Flexible Pavement Load Distribution 43

Fig.18 Rigid Pavement Load Distribution 45

Fig.19 Stress Distribution In Flexible And Rigid 46

Fig.20 Stress Distribution In Flexible And Rigid 47

Fig 21 Pavements Stress Overlap Due to Dual Wheel 47

Fig.22 Critical Line of Equal Costs (Swing Line) 50

Fig.23 Variation of CBR w.r.t % of lime 65

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LIST OF TABLES

Table 1 Cost of Flexible Pavements in Million Rupees for 48

Different Combinations of Soil and Traffic

Table 2 Cost of Rigid Pavements in Million Rupees for 49

Different Combinations of Soil and Traffic

Table 3 Stabilization methods for pavements (from rolling, 1996). 53

Table 4 Observation of coarse sieving 57

Table 5 Observation of fine sieving 58

Table 6 Physical properties of various soils 62

Table 7 Liquid limit (L.L.), plastic limit (P.L.), plasticity index (P.I.) 62

at different percentage of lime.

Table 8 variation of thickness of pavement for unstabilized soil 66

Table 9 variation of thickness of pavement for stabilized soil 66

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CHAPTER 1

INTRODUCTION

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INTRODUCTION

1.1 GeneralThe two most important factors that govern pavement design are soil sub-grade strength and

traffic loading. Depending on the strength of sub-grade soil, the layer thicknesses of flexible as

well as rigid pavements are affected. IRC:37-20015 uses soil sub-grade strength in terms of CBR

in flexible pavement; whereas IRC: 58 - 20026 uses the same in terms of modulus of sub-grade

reaction (k) for rigid pavement. The traffic load is generally estimated from 3-day axle load

survey. In the design of flexible pavements, traffic load is expressed in terms of million standard

axles (msa); whereas it is expressed in terms of axle load distribution (ALD) in design of rigid

pavements.

The present study was undertaken in two parts. In the first part, mathematical models are

developed to obtain the ALD on a highway from its vehicle volume count. The ability to convert

the soil sub-grade strength given in terms of CBR into modulus of subgrade reaction (k), and a

traffic load given in terms of msa into ALD makes it possible to design the two types of

pavements for the same soil and traffic conditions expressed differently. In the second part,

flexible and rigid pavements are designed for similar soil and traffic conditions and their costs

are compared.

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1.2 PAVEMENT

A pavement is usually a combination of several layers placed on top of an existing subgrade

(usually soil) so that vehicle loads from traffic can be transmitted safely to the subgrade without

failure or excessive damage (i.e., deformation, strain, cracking, rutting, etc.) that may affect the

serviceability of the road during the design lifespan of the pavement.

The two most important factors that govern pavement design are soil sub-grade strength and

traffic loading. Depending on the strength of sub-grade soil, the layer thicknesses of flexible as

well as rigid pavements are affected.

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1.3 PURPOSE OF PAVEMENT

Typically, pavements are built for three main purposes:

Load support:

Pavement material is generally stiffer than the material upon which it is placed, thus it assists the

in situ material in resisting loads without excessive deformation or cracking.

Smoothness:

Pavement material can be placed and maintained much smoother than in situ material. This helps

improve ride comfort and reduce vehicle operating costs.

Drainage:

Pavement material and geometric design can effect quick and efficient drainage thus eliminating

moisture problems such as mud and ponding (puddles).

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1.4 SELECTION OF TYPE OF PAVEMENT

The types of pavement generally considered for new construction and rehabilitation in California

are rigid, flexible and composite pavements. Rigid pavement should be considered as a potential

alternative for all Interstate and other high traffic volume interregional freeways. Flexiblepavement should be considered as a potential alternative for all other State highway facilities.

Composite pavement, which consists of a flexible layer over a rigid pavement have mostly been

used for maintenance and rehabilitation of rigid pavements on State highway facilities.

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1.5 Selection Criteria

Because physical conditions and other factors considered in selecting pavement type vary

significantly from location to location, the Project Engineer must evaluate each project

individually to determine the most appropriate and cost-effective pavement type to be used. Theevaluation should be based on good engineering judgment utilizing the best information

available during the planning and design phases of the project together with a systematic

consideration of the following project specific conditions:

Pavement design life

Traffic considerations

Soils characteristics

Weather (climate zones)

Existing pavement type and conditionAvailability of materials

Recycling

Maintainability

Constructibility

Cost comparisons (initial and life-cycle)

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1.6 FACTORS FOR COMPARING FLEXIBLE ANDRIGID PAVEMENT

1.6.1 BASIC ELEMENTS OF PAVEMENT

Flexible Pavement :-

A flexible pavement structure is typically composed of several layers of material

with better quality materials on top where the intensity of stress from traffic loads is high and

lower quality materials at the bottom where the stress intensity is low. Flexible pavements can be

analyzed as a multilayer system under loading.

A typical flexible pavement structure consists of the surface course and underlying

base and sub-base courses. Each of these layers contributes to structural support and drainage.

When hot mix asphalt (HMA) is used as surface course, it is the stiffest (as measured by resilient

modulus) and underlying layers are less stiff but are still important to pavement strength as well

as drainage and frost protection

Fig. 1 Typical Cross Section Of Flexible Pavement

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The Subgrade

It is the natural in situ material. The top 500 mm of subgrade should be compacted to the

desirable density near the optimum moisture content. This compacted subgrade may be the in-

situ soil or a layer of selected material.

The Base Course

The base course is the layer of materialimmediately beneath the surface or binder course. It can

be composed of crushed stone, crushed slag, or other untreated or stabilized materials.

Sub-base Course

The sub-base course is the layer of material beneath the base course. The reason that two

different granular materials are used is for economy. Instead of using the more expensive base

course material for the entire layer, local and cheaper materials can be used as a sub-base course

on top of the subgrade. If the base course is opening graded, the sub-base course with more fines

can serve as a filter between the subgrade and the base course. Sometimes the base course could

be cemented (in rigid pavement).

Prime Coat

Itis an application of low-viscosity cutback asphalt to an absorbent surface, such as an untreated

granular base on which an asphalt layer will be placed. Its purpose is to bind the granular base to

the asphalt layer.

Tack Coat

It is a very light application of asphalt, usually asphalt emulsion diluted with water, used to

ensure a bond between the surface being paved and the overlying course. It is important that each

layer in an asphalt pavement be bonded to the layer below. Tack coats are also used to bond the

asphalt layer to a PCC base or an old asphalt pavement. The three essential requirements of a

tack coat are that it must be very thin; uniformly cover the entire surface to be paved is allowed

to cure before the HMA is laid.

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The Seal Coat

It is a thin bituminous layer used to waterproof the surface or to provide skid resistance where

the aggregates in the surface course could be polished by traffic and become slippery.

Asphalt/Bitumen

Asphaltic bitumen is obtained by refining the petroleum crude. It is the costliest and a very

important component of the bituminous mix. The applicability and adhesive properties of

bitumen along with the proper proportioning with stone aggregates is the basic requirement to

make workable layer mixes.

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Layers of construction: section of 2 lanes

Fig.2 Layers Of Flexible Pavement

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Rigid Pavement:-

Rigid pavement structure is composed of a hydraulic cement concrete surface course and

underlying base and sub base courses (if used). Another term commonly used is Portland cement

concrete (PCC) pavement, although with today's pozzolanic additives, cements may no longer be

technically classified as "Portland".

The surface course (concrete slab) is the stiffest layer and provides the majority of strength. The

base or sub-base layers are orders of magnitude less stiff than the PCC surface but still make

important contributions to pavement drainage and frost protection and provide a working

platform for constructions equipment.

Rigid pavements are substantially 'stiffer' than flexible pavements due to the high

modulus of elasticity of the PCC material, resulting in very low deflection under loading. The

rigid pavements can be analyzed by the plate theory. Rigid pavements can have reinforcing steel,

which is generally used to handle thermal stresses to reduce or eliminate joints and maintain tight

crack width. Figure shows typical section for a rigid pavement.

Fig. 3 Typical Rigid Pavement

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Layers of constructions

Fig. 4 Layers Of Rigid Pavement

A typical rigid pavement structure (see Figure 3) consists of the surface course and the

underlying base and subbase courses (if used). The surface course (made of PCC) is the stiffest

(as measured by resilient modulus) and provides the majority of strength. The underlying layers

are orders of magnitude less stiff but still make important contributions to pavement strength as

well as drainage and frost protection.

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Surface Course

The surface course is the layer in contact with traffic loads and is made of PCC. It provides

characteristics such as friction (see Figure 2.3),smoothness, noise control and drainage. In

addition, it serves as a waterproofing layer to the underlying base, subbase and subgrade. The

surface course can vary in thickness but is usually between 150 mm (6 inches) (for light loading)

and 300 mm (12 inches) (for heavy loads and high traffic). Figure 2.4 shows a 300 mm (12 inch)

surface course.

Figure 5 PCC Surface

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Figure 6 Rigid Pavement Slab

(Surface Course) Thickness

The base course is immediately beneath the surface course. It provides (1) additional load

distribution, (2) contributes to drainage and frost resistance, (3) uniform support to the pavement

and (4) a stable platform for construction equipment. Bases also help prevent subgrade soil

movement due to slab pumping. Base courses are usually constructed out of:

1. Aggregate base. A simple base course of crushed aggregate has been a common

option since the early 1900s and is still appropriate in many situations today.

2. Stabilized aggregate orStabilizing agents are used to bind otherwise loose particles to

one another, providing strength and cohesion. Cement treated bases (CTBs) can be

built to as much as 20 - 25 percent of the surface course strength (FHWA, 1999).

However, cement treated bases (CTBs) used in the 1950s and early 1960s had a

tendency to lose excessive amounts of material leading to panel cracking and settling.

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3. Dense-graded HMA. In situations where high base stiffness is desired base courses

can be constructed using a dense-graded HMA layer.

4. Permeable HMA. In certain situations where high base stiffness and excellent

drainage is desired, base courses can be constructed using an open graded HMA.

Sub base Course

The sub base course is the portion of the pavement structure between the base course and the

subgrade. It functions primarily as structural support but it can also:

1. Minimize the intrusion of fines from the subgrade into the pavement structure.

2.

Improve drainage.

3. Minimize frost action damage.

4. Provide a working platform for construction.

The sub base generally consists of lower quality materials than the base course but better than the

subgrade soils. Appropriate materials are aggregate and high quality structural fill. A sub base

course is not always needed or used.

Joints

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.

(a) Contraction Joints

A contraction joint is a sawed, formed, or tooled groove in a concrete slab that creates aweakened 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, subbase 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.

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Contraction joints are chiefly defined by their spacing and their method of load transfer. They are

generally between 1/4 - 1/3 the depth of the slab and typically spaced every 3.1 - 15 m (12 - 50

ft.) with thinner slabs having shorter spacing (see Figure 2.25). Some states use a semi-random

joint spacing pattern to minimize their resonant effect on vehicles. These patterns typically use a

repeating sequence of joint spacing (for example: 2.7 m (9 ft.) then 3.0 m (10 ft.) then 4.3 m (14

ft.) then 4.0 m (13 ft.)). Transverse contraction joints can be cut at right angles to the direction of

traffic flow or at an angle (called a "skewed joint"). Skewed joints are cut at obtuse angles to the

direction of traffic flow to help with load transfer. If the joint is properly skewed, the left wheel

of each axle will cross onto the leave slab first and only one wheel will cross the joint at a time,

which results in lower load transfer stresses.

Figure 7 Rigid Pavement Showing Contraction Joints

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Figure 8 Skewed Contraction Joint

(The Tinning is Perpendicular to the Direction of Travel While the Contraction Joint is skewed)

(b) 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. Up until the 1950s, it was common practice

in the U.S. to use plain, jointed slabs with both contraction and expansion joints (Sutherland,

1956). However, expansion joint are not typically used today because their progressive closure

tends to cause contraction joints to progressively open (Sutherland, 1956). Progressive or even

large seasonal contraction joint openings cause a loss of load transfer particularly so for joints

without dowel bars.

(c) Isolation Joints

An isolation joint 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 (ACPA, 2001). They are typically filled with a joint filler material to prevent water

and dirt infiltration.

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(d) Construction Joints

A construction joint (see Figure 2.7) 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 (see Figure 2.31). Longitudinal construction joints also allow slab warping

without appreciable separation or cracking of the slabs.

Workers manually insert dowel bars into the construction joint at the end of the work day.

Construction joints should be planned so that they coincide with contraction joint spacing toeliminate extra joints.

Figure 9 - Construction Joint

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Figure 10 - Longitudinal and Transverse Construction Joints

Dowel Bars

Dowel bars are short steel bars that provide a mechanical connection between slabs without

restricting horizontal joint movement. They increase load transfer efficiency by allowing the

leave slab to assume some of the load before the load is actually over it. This reduces jointdeflection and stress in the approach and leave slabs.

Dowel bars are typically 32 to 38 mm (1.25 to 1.5 inches) in diameter, 460 mm (18 inches) long

and spaced 305 mm (12 inches) apart. Specific locations and numbers vary by state, however a

typical arrangement might look like Figure 2.34. In order to prevent corrosion, dowel bars are

either coated with stainless steel (see Figure 2.9) or epoxy (see Figure 2.36). Dowel bars are

usually inserted at mid-slab depth and coated with a bond-breaking substance to prevent bonding

to the PCC. Thus, the dowels help transfer load but allow adjacent slabs to expand and contract

independent of one another. Figure 2.10 shows typical dowel bar locations at a transverse

construction joint.

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Figure 11 - Stainless Steel-Clad Dowel Bars

Figure 12 -Dowel Bars in Place at a Construction Joint

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Tie Bars

Tie bars are either deformed steel bars or connectors used to hold the faces of abutting slabs in

contact Although they may provide some minimal amount of load transfer, they are not designed

to act as load transfer devices and should not be used as such Tie bars are typically used at

longitudinal joints or between an edge joint and a curb or shoulder. Typically, tie bars are about

12.5 mm (0.5 inches) in diameter and between 0.6 and 1.0 m (24 and 40 inches long).

Reinforcing Steel

Reinforcing steel can also be used to provide load transfer. When reinforcing steel is used,

transverse contraction joints are often omitted Therefore, since there are no joints, the PCC

cracks on its own and the reinforcing steel provides load transfer across these cracks. Unlikedowel bars, reinforcing steel is bonded to the PCC on either side of the crack in order to hold the

crack tightly together.

Typically, rigid pavement reinforcing steel consists of grade 60 (yield stress of 60 ksi (414 MPa)

No. 5 or No. 6 bars The steel constitutes about 0.6 - 0.7 percent of the pavement cross-sectional

area and is typically placed at slab mid-depth or shallower. At least 63 mm (2.5 inches) of PCC

cover should be maintained over the reinforcing steel to minimize the potential for steel

corrosion by chlorides found in deicing agents .

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1.6.2 DESIGN OF PAVEMENT

A. Design Of Flexible Pavement :-

The thickness of pavement is designed on the basis of projected number of commercial

vehicles for the design life using the current commercial vehicles per day and its growth rate.

Further, it requires the sub grade strength value is term of CBR. It is expected that rural road

will not have more than 450 CBPD in any case. The design chart given in Figure-3 may be

referred to obtained the total pavement crust thickness (granular curst thickness) required

over the sub-grade for the design life of the pavement. Based on the strength of granular

materials the are used, the total design thickness is divided into base and sub base thickness.

However any other higher type of bituminous layer can be part of the designed thickness.

However, any other higher type of bituminous layer can be part of the designed thickness,

with exception of thin bituminous surfacing (PMC, MSS, etc). In case of rural roads with low

volume of traffic, structural layer bituminous mix and not be provided, generally except is

very special cases where the traffic volume is so high that the design suggest it whole range

of traffic and CBR that exist for rural roads in various States of the country have been

considered and flexible pavement thickness catalogues are given in Figures-14,15,16 for

ready reference.

Fig.13: CBR Curve For Flexible pavement Design

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A B C D

A B C D

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A B C D

Sub Base Course Base Course Surfacing

Fig 14: Thickness of crust required for different traffic

A

B

C

D

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A B C D

A B C D



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A B C D

A B C D

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A B C D



TYPICAL CROSS-SECTION OF ROAD

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B. Design Of Rigid Pavement:-

Design the following details of a plain cement concrete pavement for a two lane highway.

(a)Pavement slab thickness

(b)Dowel bars for expansion joints

(c)Tie bars for longitudinal joints

Follow the design procedure recommended by IRC where ever applicable. Use the given data,

IRC load stress charts for edge and corner regions, and assume any other data not provided here.

Width of expansion joint gap = 2.5 cm

Maximum variation in temperature between

summer and winter = 35 C

Thermal coefficient of concrete = 10x10" per C

Allowable tensile stress in CC during curing = 0.8 kg/cm

Coefficient of friction = 1.5

Unit weight of CC = 2400 kg/cm3

Design wheel load - 5100 kg

Radius of contact area = 15 cm

Present traffic intensity, = 950 commercial vehicles/day

Modulus of reaction of sub-base course = 8 kg/cm3

Flexural strength (allowable flexural stress) of concrete = 40 kg/cm2

E value of concrete = 3 x 105kg/cm

2

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/ \ivalue = 0.15

Design load transfer through dowel system = 40%

Permissible flexural stress in dowel bar = 1400 kg/cm2

Permissible shear stress in dowel bar - 1000 kg/cm2

Permissible tensile stress in steel (tie bar) = 1400 kg/cm2

Permissible bond stress in deformed (tie bars) = 24.6 kg/cm2

Temperature differential values in the region:

Slab thickness, cm 15 20 25

Temperature differential in slab in the region, C 14.6 15.8 16.3

(a) Joint Spacing

1joint 2.51.25cm2 2

Spacing of expansion joint Ls

1.25

35.7m100C(T 100x10x10

x35T )

2 1

which is less than maximum specified spacing of 140 m and so acceptable. Contraction joint

spacing in plain CC,

Lc=2S

c

x104

2x0.8x1044.45m

W.f 2400x1.5

which is less than maximum specified spacing of 4.5 m and hence acceptable.

Therefore provide contraction joints at 4.45 m spacing and expansion joints at every 8th such

joints i.e., 4.45 x 8 = 35.5 m spacing (instead of 35.7 m)

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Cx= 0.80 (from chart Fig. 7.25); Cyat Ly// of 4.29 = 0.6

Temperature differential for 24 cm thick slab (by interpolation) = 16.2C

Ste =1/2 x3x 105xl 0 x 10

-6x 16.2x0.8 = 19.44 kg/cm

2

Residual strength at the edge

= 40.0-19.44 = 20.56 kg/cm2

Load stress at edge, using stress chart (Fig. 7.23)

for h = 4,K = 8,Se=19.2kg/cm2

Factor of safety available 20.56

1.07which is safe and acceptable value19.2

Therefore provide a tentative design thickness of 24 cm.

Check for comer load stress : Using IRC stress chart Fig. 7.24, for h = 24, K = 8, the value of Sc

= 23.0 kg per cm .

Comer warping stress Ste=

E.e.t. 1

3(1 ) l

3x155x10x10

6x16.2

15

7.1kg/ cm2

3(10.15) 81.53

The worst combination of stresses at the comer is 23.0 + 7.1 = 30.1 kg/cm2, which is also less

than the allowable flexural strength of 40 kg/cm and hence the design is safe.

Adjustment for Trafficintensity Ad= P'[(l+r)]

(n+20)

Assuming a growth factor r = 7.5% and the number of years after the last count before the new

pavement is opened to traffic, n = 3.

Ad=9507.5 (n20)

1 5013cv/ day100

This traffic intensity being in the range > 4500, falls in group G and die adjustment factor is + 2

cm.

Therefore the revised design thickness of the slab

= 24 + 2 = 26 cm (c)

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(c)Dowel bars

Assume dowel bar diameter = 2.5 cm

Joint width, 8 = 2.5 cm

For Equal capacity in bending and bearing

1F (L

d 1.5)Ld =5d 1xF

b (Ld 8.8) 1

1400 L 1.5x2.5=5x2.5

d

100 Ld8.8x2.5

By substituting different values of Ld by trials (as in Example 7.22), the value of Ldi found to be

42.2 cm.

Length of dowel bar = Ld+ = 42.2 + 2.5 = 44.7 cm Therefore provide 45 cmlong dowel bars of diameter 2.5 cm

Actual value of Ld+ 45.0 - 2.5 = 42.5 cm Load transfer capacity of single

dowel:

P'(shear) = 0.785 d2Fs

= 0.785 x 2.52x 1000 = 4906 kg

2d2F 2x2.5

5x1400

P' (bending) 1 678kgLd8.8 42.5 8.8x2.5F .L .d 100x42.5 x2.5

P' (baring) b d 781kg12.5(Ld1.5) 12.5(42.5 1.5x2.5)

Taking the lowest value for design, P (design) =678 kg.

Load capacity factor required:

40

Load capacity of the dowel group = 5100 x -----= 2040 kg

100

Capacity factor required = =3.0

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Spacing of dowel bars :

Radius of relative stiffness for revised slab thickness o 1 24 cm,

3x105x26

3 14

l 86.6cm2)12x8(1 0.15

Effective distance up to which there is load

transfer = 1.8 /= 1.8x86.6 155.9 cm

Assuming a trial spacing of 35 cm between the dowel bars, the capacity available for the group

1 155.9 35

155.9 70

155.9 105

155.9 140

155.9 155.9 155.9 155.9

= 2.77< the required value of 3.0.

Assume dowel bar spacing of 30 cm.

155.9-30155.9-60155.9-90 ,

Capacity factor = 1 + ------- + ------ -----' ------------ +

As this value is greater than the required capacity factor of 3.0, 30 cm spacing of the dowel bars

is adequate. Therefore provide 2.5 cm dia. Dowel bars at expansion joints, of total length 45 cm

at a spacing of 30 cm centres.

(d) Tie Bars

Area of steel .per metre length longitudinal joint,b.f.h.W 3.5x1.5x26x2400 , ,

As=............... = .......................... = 2.34 cm2per m length

100SSS100x1400

Assuming 1 cm diameter of the bars, cross sectional area of each tie bar as =

0.785cm2. Perimeter of the tie bar = 3.14cm

Number of tie bars required per meter length of joint

A

s

2.342.98as0.785

Spacing of tie bar = -------------- = 33.5 cm

Provide a spacing of tie bar, say 33 cm

The length of tie bar may be increased by 5 cm for tolerance in placement.

Therefore provide 1 cm diameter deformed tie bars, 34 cm in length at a spacing of 33 cm.

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1.6.3 ADVANTAGES OF PAVEMENT

Flexible pavement

Load is transferred by grain to grain contact

Force of friction is less deformation in the sub grade is not transferred to the upper layers.

Expansion joints are not needed

Road can be used for traffic within 24 hours

No thermal stresses are induced as the pavement have the ability to contract and expand

freely

Have low completion cost

Design is based on load distributing characteristics of the component layers

Deformation in the sub grade is transferred to the upper layers

Rigid pavement

Design is based on flexural strength or slab action

Have high flexural strength

Deformation in the subgrade is not transferred to subsequent layers

No such phenomenon of grain to grain load transfer exists

Rolling of the surfacing in not needed

Have low repairing cost

Life span is more

Surfacing can be directly laid on the sub grade

No damage from oils and greases.

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1.6.4 LIMITATIONS OF PAVEMENT

Flexible pavement

Have low flexural strength

Surfacing cannot be laid directly on the sub grade but a sub base is needed

Strength of the road is highly dependent on the strength of the sub grade

Repairing cost is high

Rolling of the surfacing is needed

Have low life span

Rigid pavement

Thermal stresses are more vulnerable to be induced as the ability to contract and expand

is very less in concrete

Expansion joints are needed

Strength of the road is less dependent on the strength of the sub grade

Road cannot be used until 14 days of curing

Force of friction is high

Completion cost is high

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1.6.5 LOAD DISTRIBUTION

Flexible Pavement:-

Flexible pavements are so named because the total pavement structure deflects, or flexes, under

loading. A flexible pavement structure is typically composed of several layers of material. Each

layer receives the loads from the above layer, spreads them out, then passes on these loads to the

next layer below. Thus, the further down in the pavement structure a particular layer is, the less

load (in terms of force per area) it must carry.

Figure 17: Flexible Pavement Load Distribution

In order to take maximum advantage of this property, material layers are usually arranged in

order of descending load bearing capacity with the highest load bearing capacity material (and

most expensive) on the top and the lowest load bearing capacity material (and least expensive)

on the bottom. This section describes the typical flexible pavement structure consisting of:

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Surface course. This is the top layer and the layer that comes in contact withtraffic. It

may be composed of one or several different HMA sub layers.

Base course. This is the layer directly below the HMA layer and generally consistsof

aggregate (either stabilized or unstabilized).

Subbase course. This is the layer (or layers) under the base layer. A subbase is

notalways needed.

Rigid Pavement:-

Rigid pavements are so named because the pavement structure deflects very little under loading

due to the high modulus of elasticity of their surface course. A rigid pavement structure is

typically composed of a PCC surface course built on top of either (1) the subgrade or (2) an

underlying base course. Because of its relative rigidity, the pavement structure distributes loads

over a wide area with only one, or at most two, structural layers

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Figure 18: Rigid Pavement Load Distribution

This section describes the typical rigid pavement structure consisting of:

Surface course. This is the top layer, which consists of the PCC slab.

Base course. This is the layer directly below the PCC layer and generally consists

ofaggregate or stabilized subgrade.

Sub base course. This is the layer (or layers) under the base layer. A sub base is

notalways needed and therefore may often be omitted.

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Comparison:-

The primary structural difference between a rigid and flexible pavement is the manner in

which each type of pavement distributes traffic loads over the sub-grade. A rigid pavement has a

very high stiffness and distributes loads over a relatively wide are of sub-grade a major portion

of the structural capacity is contributed by the slab itself.

Fig.19 Stress Distribution In Flexible And Rigid

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Fig.20 Stress Distribution In Flexible And Rigid

Fig. 21 Pavements Stress Overlap Due to Dual Wheel

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1.6.6 COSTING OF PAVEMENT

Flexible Pavement

The costs of different pavements are obtained by multiplying the volumes of materials by their

respective costs. The costs of the different materials were calculated using 2006 schedule of rates

for Dehradun district. Bageshwar Prasad2 used a maintenance cost of Rs 1.5 million for flexible

pavements and the same was uniformly added to all the pavements in this study. Therefore, the

costs computed in this study include both construction and maintenance costs. Table 3 gives the

costs of flexible pavements designed for different combinations of soil CBR and traffic

conditions. Fig shows the variation in cost of flexible pavements with respect to traffic loading.

Equation relates the cost of flexible pavements with soil CBR and traffic loading.

Cost = -16.98+12.136*CBR

-0.3

+15.476*msa

0.10

Table 1 Cost of Flexible Pavements in Million Rupees for Different Combinations of Soil

and Traffic

Soil Traffic Load(msa)

CBR 1 2 3 5 10 20 30 50 100 150

%

2 7.12 8.49 9.09 10.67 12.60 14.29 15.25 16.32 18.00 18.85

3 7.12 7.69 8.28 9.45 11.51 13.19 14.14 15.33 16.77 17.49

4 5.80 7.18 7.76 9.17 11.01 12.33 13.29 14.58 16.14 16.74

5 5.45 6.682 7.39 8.67 10.56 11.76 12.59 13.77 15.08 15.68

6 5.17 6.53 7.11 8.26 10.03 11.23 11.94 12.88 14.07 14.78

7 5.07 6.36 6.89 8.04 9.81 10.77 11.60 12.54 13.72 14.56

8 5.07 6.36 6.82 7.83 9.59 10.56 11.27 12.20 13.39 14.22

9 5.07 6.36 6.82 7.83 9.48 10.21 10.91 11.97 13.15 13.98

10 5.07 6.36 6.82 7.83 9.48 10.21 10.80 11.62 12.91 13.75

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Rigid Pavement

The cost of construction and maintenance are considered in this study. The cost of sub-grade, dry

lean concrete sub-base, pavement quality concrete slab, shoulders, dowel bars, and tie bars were

computed as per 2006 schedule of rates for Dehradun district. Maintenance cost is adopted from

a study made by Bageshwar Prasad2. The total cost of construction and maintenance costs for all

the pavements are shown in Table 4. Fig. 10 shows the cost of rigid pavements against traffic

loading for different values of sub-grade CBR. Equation 14 was developed using multiple

regression analysis.

Cost = 8.284 + 4.719 * CBR-0.9

+ 20.8 * msa0.15

Table 2 Cost of Rigid Pavements in Million Rupees for Different Combinations of Soil and

Traffic

Soil Traffic Load (msa)

CBR % 7 10 20 30 50 100 150

2 13.32 13.92 13.92 14.54 14.85 15.15 15.15

3 12.41 13.01 13.01 13.63 13.93 14.24 14.24

4 12.15 12.74 12.74 13.36 13.36 13.66 13.96

5 11.87 12.46 12.46 13.07 13.37 13.37 13.69

6 11.87 12.19 12.48 13.09 13.09 13.39 13.39

7 11.90 12.19 12.50 12.80 13.09 13.41 13.41

8 11.61 12.21 12.21 12.82 12.82 13.11 13.41

9 11.64 11.92 12.24 12.53 12.82 13.13 13.13

10 11.36 11.95 11.95 12.53 12.53 12.84 13.13

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COMPARISON:-

The design and cost computations for flexible and rigid pavements are discussed in Sections 3

and 4 respectively. The initial aim of this study was to determine the threshold values of CBR

and msa beyond which one of the pavements becomes economical in its combined construction

and maintenance cost. The points of equal cost on the CBR vsmsa graph were determined using

Equations 13 and 14 and these are plotted in Fig.11. Rigid pavements are found to be economical

in the upper portion of the graph and flexible pavements are economical in the lower portion of

the graph. Mathematically:

If msa12.48+6.05 x CBR, rigid pavement will be economical;

If msa=12.48+6.05 x CBR, both pavements will have the same cost.

The above mathematical equation is developed by fitting a straight line to the points of equal

costs. It has an R2 value of 0.998. The equation is valid for soil CBR values ranging from 2

percent to 10 percent.

Fig.22 Critical Line of Equal Costs (Swing Line)

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1.7 Considerations for Flexible vs. Rigid Pavements

Explains how the state Departments of Transportation have begun to implement the

practice of including rigid versus flexible pavement structure alternatives in construction plans in

order to provide flexibility in contractor competition. Ideally, the inclusion of alternate pavementdesigns early in the bidding process would allow DOTs to achieve a best -value bid price, but

there is concern that alternative pavement designs might not be truly equivalent. Several Life-

Cycle Cost Analysis (LCCA) studies have been conducted in order to determine whether the

alternate designs included in contracts will display comparable performance lives. In California,

pavement design alternatives are analyzed for design lives of 10, 20, and 40 years, in order to

determine the most cost-effective alternate pavement design life. Furthermore, the Colorado

Department of Transportation recommends a 40-year analysis period when comparing flexible

and rigid pavements, and the Alternate Design Alternate Bid (ADAB) procedure developed by

the Louisiana DOT appears to have been adopted as standard industry practice. This protocol

includes an analysis of general project information, an LCCA comparison of flexible and rigid

pavement designs, and a final engineering project evaluation. Equivalent pavement designs

should be considered for major highway projects, and projects with a high volume of trucks.

why one pavement is used versus another. Basically, state highway agencies generally

select pavement type either by policy, economics or both. Flexible pavements generally require

some sort of maintenance or rehabilitation every 10 to 15 years. Rigid pavements, on the other

hand, can often serve 20 to 40 years with little or no maintenance or rehabilitation. Thus, it

should come as no surprise that rigid pavements are often used in urban, high traffic areas. But,

naturally, there are trade-offs. For example, when a flexible pavement requires major

rehabilitation, the options are generally less expensive and quicker to perform than for rigid

pavements.

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1.8 SOIL STABILIZATION

1.8.1Type Of stabilization

Remove and replace

Lime Piles Mechanical stabilization

Admixture Stabilization (cement, lime, fly ash,bituminous)

1.8.2Pavement Performance (Lime-Stabilized Subgrades and Base/Sub base Layers)

The material properties of both lime-stabilized soils and lime-stabilized aggregates, as related to

their impact on overall pavement performance, can be divided into four categories (Little, 1999):

StrengthThe most obvious improvement in a lime-reactive soil or aggregate is strength

gain over time. The various strength parameters impacted by the pozzolanic reactions that

occur include unconfined compressive strength, tensile strength, flexural strength, and

CBR

Resilient modulus/stiffnessConcurrent with the strengthening of a soil brought about by

pozzolanic reactions, are changes in the stressstrain relationship of the material . Lime-

stabilized soils fail at much higher deviator stresses than their no stabilized counterparts,

and at a much lower strain (typically about 1 percent strain for the stabilized mixture

versus about 3 percent for the no stabilized material). Materials tested in the laboratory

(repeated-load triaxial and indirect tensile tests) and in the field (impulse deflection

testing, vibrational testing) both confirm significant increases over time in the resilient

properties of lime-treated materials

Fracture and fatigueFlexural fatigue strength is related to the number of loads that can be

carried by a material at a given stress level, and it is an important consideration in theevaluation of limesoil and limeaggregate mixtures. The strength-gain effects produced

by pozzolanic reactions are often substantial for reactive soils.

DurabilityThe ability of lime-stabilized materials to resist the detrimental effects of

moisture and freeze-thaw cycling over time has been evaluated in several ways, in both

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the laboratory and the field. The results of these evaluations have often shown only slight

detrimental effects of environment on the levels of strength/stiffness produced by the

addition of lime.

Table 3. Stabilization methods for pavements (from rolling, 1996).

Method Soil Effect Remarks

Blending Moderately None Too difficult to mixplastic

Others Improve gradation

Reduce plasticity

Reduce breakage

Lime Plastic Drying Rapid

Immediate strength gain Rapid

Reduce plasticity Rapid

Coarsen texture Rapid

Long-term pozzolanic Slow

cementing

Coarse with Same as with plastic soils Dependent on quantity of

fines plastic fines

Non plastic None

Cement Plastic Similar to lime Less pronounced

Cementing of grains Hydration of cement

Coarse Cementing of grains Hydration of cement

Bituminous Coarse Strengthen/bind, Asphalt cement or liquidwaterproof asphalt

Some fines Same as coarse Liquid asphalt

Fine None Can't mix

Pozzolanic and Silts and coarse Acts as a filler Denser and strongerSlags

Cementing of grains Slower than cement

Misc. methods Variable Variable Depends on mechanism

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CHAPTER 2

EXPERIMENTAL PROGRAMME

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2.1 SOIL PROPERTIES

2.1.1 Water Content/Moisture Content (w)

w = *100

w = * 100

2.1.2 Degree Of Saturation (s)

S = * 100

0 < S < 100%

2.1.3 Void Ratio (e)

e = * 100

2.1.4 Porosity (n)

n = * 100

0 < n < 1

2.1.5 Air Content (a)

a =

a + S = 1

2.1.6 Specific Gravity (G)

G=

2.1.7Density 2.1.7.1

Bulk Density

t =

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2.2 PARTICLE SIZE DISTRIBUTION (Sieve analysis)

2.2.1 Coarse Sieving

Sieves having square opening are arranged there decreasing size from top to bottom. The sieve

used are80mm , 20mm , 10mm ,&4.75mm the sample is shaken for 10min by hands

Table 4 Observation of coarse sieving

S.no Sieve no. Mass retain % Retain % Cumulative % passing

(gms) retain

1. 80mm 0 0 0 100%

2. 40mm 470gm 9.40 9.40 90.60

3. 20mm 925gm 18.50 27.90 72.10

4. 10mm 1412gm 28.24 56.14 43.60

5. 4.75mm 976gm 19.50 75.64 24.36

6. Pan 1219gm 24.36 100 0

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2.2.2 Fine Sieving

The particles passing from 4.75m sieve are further analyzed and the sieve of 2mm , 1mm, 6oo,

425, 212, 150, 75 are arranged in decreasing order.

Table 5 Observation of fine sieving

S.no Sieve no. Mass retain % Retain % Cumulative % passing

(gms) retain

1. 2mm

2. 1mm

3. 600

4. 425

5. 212

6. 150

7. 75

8. Pan

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2.3 CBR TEST

INTRODUCTION

The California Bearing Ratio, believe it or not, was developed by The California State HighwaysDepartment.It is in essence a simple penetration test developed to evaluate the strength of roadsubgrades. CBR-value is used as an index of soil strength and bearing capacity. This value isbroadly used and applied in design of the base and the sub-base material for pavement.

THE BASIC CBR TESTThis consists of causing a plunger of standard area to penetrate a soil sample, (this can be in the

laboratory or on site). The force (load) required to cause the penetration is plotted against

measured penetration, the readings noted at regular time intervals.

This information is plotted on a standard graph, and the plot of the test data will establish the

CBR result of the soil tested.

THE REASON FOR THE CBR TEST

It sounds complicated, but the basis behind it is quite simple.

We are determining the resistance of the subgrade, (i.e. the layer of naturally occurring material

upon which the road is built), to deformation under the load from vehicle wheels.

Even more simply put, ''How strong is the ground upon which we are going to build the road''.

The stronger the subgrade (the higher the CBR reading ) the less thick it is necessary to design

and construct the road pavement, this gives a considerable cost saving.

Conversely if CBR testing indicates the subgrade is weak (a low CBR reading) we must

construct a suitable thicker road pavement to spread the wheel load over a greater area of the

weak subgrade in order that the weak subgrade material is not deformed, causing the road

pavement to fail.

CBR VALUE SUBGRADE STRENGTH COMMENTS

3% and less Poor " Capping is required

3%- 5% NormalWidely encountered CBR range cappingconsidered according to road category

5%- 15% Good"Capping" normally unnecessary except on veryheavily trafficked roads.

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2.3.1 CBR of unstabilized soil

CBR-values of untreated compacted soils need to be interpreted in the context of the general

relationship between the CBR-values and the consistency (quality) of the soils used in pavement

applications (Bowles, 1992). CBR-values ranging from 3 to 7% are considered as a poor to fairconsistency.

2.3.2 CBR of stabilized soil

Soil-lime mixtures of the three tested soils were prepared at the optimum lime content,

2%, and 4% above the optimum lime content and cured for 7 days.

The addition of the optimum lime content led to an increase in the CBR-values for the three

tested soils. The lime-tertiary clay mixtures have the highest CBR-values, whereas the lime-

weathered soil mixtures have the lowest values. The reactivity of the tertiary clay with lime is

stronger than the reactivity of both the weathered soil and the organic silt. The CBR -values of

lime-tertiary clay mixtures increased slightly with increasing lime content (2 and 4% above the

optimum lime content).

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CHAPTER 3

RESULTS

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Table 6 Physical properties of various soils

S. Properties Banga Garshankar Nawanshahar

No. Garshankar road Nawanshahar road Phagwara road soilsoil soil

1. Plasticity Clay of low Plasticity Clay of low Plasticity Clay of low plasticity

2. Specific gravity (G) 2.58 g/cm3 2.40 g/cm3 2.55 g/cm3

3. Liquid limit L. L 32.5% . 27% 31%

4. Plastic limit P. L. 14.5% 18% 17%

5. Plasticity index P. I. 18% 9% 14%

6. Optimum moisture

Content (OMC) 14% 14% 12%

7. Maximum dry density 1.72 g/cm3 1.68 g/cm3 1.75 g/cm3

Table 7. Liquid limit (L.L.), plastic limit (P.L.), plasticity index (P.I.) atdifferent percentage of lime

S. No. Percentage of Banga- Garshankar Nawanshahar-

Lime Garshankar Nawanshahar PhagwaraRoad soil road soil road soil

L.L. P.L. P.I. L.L. P.L. P.I. L.L. P.L. P.I.

1 0 32.0 18.0 14.0 27.0 18.0 9.0 31.0 17.0 14.0

2 1 32.8 26.0 6.8 33.0 27.0 6.0 31.3 24.0 7.3

3 2 33.0 29.0 4.0 36.0 30.5 5.5 31.5 28.0 3.5

4 3 33.0 30.5 2.5 36.5 31.5 5.0 31.5 29.5 2.0

5 4 33.0 31.0 2.0 36.9 32.2 1.7 31.5 30.0 1.5

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3.2 Benefits of stabilization

Lower material costs

when soil stabilization is taken into account during the pavement design, a significant

reduction in the required amount of base thickness and pavement surface materials willresult

Lower construction costs

when compared to traditional methods of complete removal and replacement or

traditional undercuts, a cost savings of 30 to 50 percent may be achieved

Reduced logistics costs and increased environmental responsibility

stabilizing the existing soil eliminates the need to export the poor undesirable soils or

import new usable fill material

Increased strength

a dramatic increase in CBR (California Bearing Ratio) can be achieved, changing

unstable CBR values of 7 or less into highly stable CBR values

Longer durability

stabilized soil is highly resistant to water and frost (often the main causes of pavement

failure), which increases the lifespan of the subgrade

Safer operations

the improved soil surface reduces the risks associated with persons slipping and falling,

vehicles skidding, collisions and other accidents; emergency vehicles are able to travel

the finished subgrade without restraint

More reliable construction

stabilized fills are less likely to suffer trench cave-ins and undesirable shifting of

construction elements

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Greater convenience

in many circumstances, roads that are stabilized do not have to be shut down to traffic;

even before they are paved, stabilized soil surfaces support foot and vehicle traffic, which

helps to virtually eliminate complaints from nearby residents, employees and visitors

3.2.1 Analysis of results for physical properties of soil with lime stabilization

It is observed from Table 2 that with increase in lime content, optimum moisture

content increases and maximum dry density decreases

The liquid and plastic limit increased sharply for all the samples with lime content up to

2 per cent and the increase was negligibly small beyond 2 per cent lime content.

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3.3 Effects on CBR value due lime stabilization

3.3.1 CBR of Soil +20% lime

The results of CBR tests for soil with 20% lime for three samples at different compaction efforts

(10, 30 and 65 blows. By plotting the results as discussed earlier, the CBR value is determined

at 25 blows to be 15.

3.3.2 CBR of Soil +30% lime

The results of CBR tests for soil with 30% lime for three samples at different compaction

efforts (10, 30 and 65 blows). By plotting the results as discussed earlier, the CBR value is

determined at 25 blows to be 18.

Fig 23 Variation of CBR w.r.t % of lime

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Table 8. Variation of thickness of pavement for unstabilized soil

Table 9. Variation of thickness of pavement for stabilized soil

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CHAPTER 4

CONCLUSION

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It is observed with increase in lime content, optimum moisture content increases

and maximum dry density decreases.

The liquid and plastic limit increased sharply for all the samples with lime content upto

2 per cent and the increase was negligibly small beyond 2 per cent lime content.

The problem of settlement of roads is prevalent due to soil stabilization.

If CBR value is found maximum without stabilization flexible pavement provided as

for economically.

If CBR value is found minimum without stabilization rigid pavement provided as

for good strength and economically.

If the soil is stabilized than the problem for settlement is prevents for any type

of pavement.

For required thickness of soil 2% of lime is required for addition.

Soil properties have been improved with soil stabilization.

Permeability decreased.

Improvement in soil properties by adding Lime.

Effect of lime is less for cohesion less soils.

Curing Period increase in fatigue life up to 4 to 6 weeks of curing.

The road constructed with enzyme stabilized soil has monitored for its performance at

regular interval for 8-10 months. The road is performing well and field CBR test

indicates that stabilized soil can be used as sub base material very effectively. But prior

laboratory study is necessary to get the good result in the field

Geotechnical properties of soil are increasing by stabilization of soil.

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References

http://www.civil.iitb.ac.in/~dns/IACMAG08/pdfs/N13.pdf

Research paper- Jordan Journal of Civil Engineering, Volume 6, No. 1, 2012

Research paper- highway research journal Vol 5 - No 2.

Research paper- Comparative Study of Flexible and Rigid Pavements For Different

Soil and Traffic Conditions.

Indian Standard handbook for civil engineers by: Khanna

HIGHWAY ENGINERRING BY : S.K. Khanna, C.E.G. Justo

Highway material testing laboratory manual by: S.K. Khanna

Ministry of Road Transport And Highway 4th Revised Publish By IRC (New

Delhi) 2001.

ER.Yogesh Sharma

ER. Pushpendra Sir

Documents

Prm minor_project.pdf.docx