This document discusses the design and construction of pavements. It begins by defining the two main types of pavements - flexible (or bituminous) pavement and rigid (or cement concrete) pavement. It then provides details on the components, materials, construction methods, and factors affecting the selection of each pavement type. The document also covers topics like soil stabilization, construction of embankments, subgrades and various pavement layers. Overall, the document provides a comprehensive overview of pavement design and construction processes.

1. “DESIGN AND
CONSTRUCTION OF
PAVEMENT”
1
PREPARED BY : ASST. PROF. VATSAL D. PATEL
MAHATMA GANDHI INSTITUTE OF
TECHNICAL EDUCATION &
RESEARCH CENTRE, NAVSARI.

2. PAVEMENT
 Pavement is the durable surface material laid down on an
area intended to sustain vehicular load or foot traffic, such
as a road or walkway.
 It is of two types :
 Flexible pavement or bituminous pavement or black top
pavement
 Rigid pavement or cement concrete pavement or white
surface pavement

3. FLEXIBLE PAVEMENT
 The pavement which possess low flexural strength (bending
strength) and can transfer the wheel loads on the soil sub
grade below by deformation action is called flexible
pavement.
 For example, Bituminous roads, Stabilized soil roads, WBM
roads, Earth/ Gravel roads.

4. RIGID PAVEMENT
 The pavement which possess low flexural strength and can
transfer the wheel loads on the soil sub grade below
without deformation of pavement is called rigid pavement.
 For example, Cement concrete roads, RCC roads,
Prestressed concrete roads

5. COMPARISON OF FLEXIBLE
PAVEMENT & RIGID PAVEMENT
FLEXIBLE PAVEMENT RIGID PAVEMENT
Have low flexural strength Have more flexural strength
Load is transferred by grain to grain
contact
No such phenomenon of grain to grain
load transfer exists
Surfacing cannot be laid directly on the
sub grade but a sub base is needed
Surfacing can be directly laid on
the sub grade
No thermal stresses are induced Thermal stresses are induced
Expansion joints are not needed Expansion joints are needed
Design life 10-15 years Design life 20-30 years
Initial cost of construction is low Initial cost of construction is high
Maintenance cost is high Less maintenance cost
Road can be used for traffic within 24
hours
Road cannot be used until 14 days of
curing
Damaged by Oils and Certain Chemicals No Damage by Oils and other chemicals

6. FACTORS AFFECTING SELECTION
OF PAVEMENT
 Type and intensity of traffic
 Availability of fund for the construction and maintenance of
highway
 Sub grade soil and drainage condition
 Availability of construction material
 Availability of equipment, skilled and unskilled labors etc
 Atmospheric conditions like amount of rainfall, snowfall etc
 Time available for the completion of the project
 Level of the area above mean sea level

7. FUNCTION OF PAVEMENT
COMPONENTS
 The various components of pavement are as below:
1. Subgrade
2. Sub base
3. Base course
4. Wearing course or surface course

8. FACTORS AFFECTING SELECTION
OF PAVEMENT
 Subgrade :
 The soil sub grade is a layer of natural soil prepared to
received the layers of pavement materials placed over it.
 The loads on pavements are ultimately received by the soil
subgrade for dispersion to the earth mass. It is essential
that at no time, the subgrade soil is overstressed.
 The pressure on the subgrade should not exist its elastic
limits. Therefore it is desirable that at least top 50 cm layers
of the sub grade soil is well compacted under controlled
conditions of the optimum moisture content (OMC) and
maximum dry density (MDD).

9. FACTORS AFFECTING SELECTION
OF PAVEMENT
 Sub base :
 A layer of broken stones, sand, gravel, moorum, etc of
about 30 cm thickness is laid over the compacted sub
grade. This layer is called sub base.
 Sometimes in sub base course a layer of stabilized soil or
selected granular soil is also used. In some places, boulder
or bricks are also used as sub base course.

10. FACTORS AFFECTING SELECTION
OF PAVEMENT
 Base course:
 The layer immediately below the wearing course of
pavement is called base course.
 The bases courses consists of local soft aggregates,
stabilized soil, WBM, bricks, slag etc.
 Its thickness varies from 7.5 cm to 10 cm. The width of base
course is normally kept 30 cm more than the width of
wearing course on each side.

11. FACTORS AFFECTING SELECTION
OF PAVEMENT
 Wearing course or surface course :
 The upper most layer of the pavement is called wearing
course.
 It should be impermeable.
 It consists of low-cost surface, bituminous surface or
cement concrete surface.

12. FACTORS TO BE CONSIDERED IN
PAVEMENTS
 Flexible pavement :
 Mix design of materials to be used in each pavement
component layer
 Thickness design of pavement
 Rigid pavement :
 Wheel loads of heavy vehicles
 Subgrade soil
 Climatic factors
 Pavement component materials in different layers
 Drainage and environmental factors

13. RIGID PAVEMENT AS PER IRC
GUIDELINES
 General consideration :
 Cement concrete pavement represent the group of rigid
pavements.
 The load carrying capacity of cement concrete pavement is
mainly due to the rigidity and high modulus of elasticity of
the slab i.e. Slab action.
 Westergaard is considered the pioneer in providing the
rational treatment of the problem of rigid pavement
analysis.

14. RIGID PAVEMENT AS PER IRC
GUIDELINES
 Modulus of sub-grade reaction:
 Westergaard considered the rigid pavement slab as thin
elastic plate resting on soil sub-grade, which is assumed as
a dense liquid. It is assumed that the upward reaction is
proportional to the deflection. i.e.
 P = k∆
 Where, k = constant (modulus of sub-grade reaction)
 The unit of k is kg/cm2 per cm deflection

15. RIGID PAVEMENT AS PER IRC
GUIDELINES
 Relative stiffness of slab to sub-grade :
 A certain degree of resistance is offered by the sub-grade to
slab deflection. This is dependent upon the stiffness of the
sub-grade material.
 The tendency of the slab to deflect is dependent upon the
flexural strength of slab.

16. STEPS FOR CONSTRUCTION OF HIGHWAY
ON EMBANKMENT
 Clearing the vegetation, roots, and other organic matter
along the alignment of highway up to bottom width of the
embankment and the side drains.
 Re-compaction of the natural ground that supports the to
the specified density.
 Selected soil is spread and compacted in layers to form the
embankment of specified height.
 Excavation for the longitudinal side drains.
 Construction of cross drainage structure.
 Laying of drainage cum granular sub base layer over the
sub-grade.

17. STEPS FOR CONSTRUCTION OF HIGHWAY
IN CUTTING
 Excavation of earth up to the desired with specified side
slope along the alignment.
 Compaction of the bottom of the cutting as specified.
 Excavation of longitudinal side drain.
 Construction of sub grade as specified.
 Laying of drainage cum granular sub base layer over the
sub grade.
 Building up of shoulders in layers.
 Finishing works are specified.

18. CONSTRUCTION OF EMBANKMENT
 When it is required to raise the grade line of a highway
above the existing ground level, it becomes necessary to
construct embankment or fill.
 Construction method :
 The selected soil in loose condition is spread to uniform
thickness using appropriate equipment such as blade
grader over the prepared ground. The thickness of the
smooth soil layer is decided so as to obtain the specified
compacted thickness of layer, determined during proof
rolling.

19. CONSTRUCTION OF EMBANKMENT
 Additional water as required is sprayed over the loose soil
layer so as to obtain the OMC of the soil determined from
the laboratory compaction test. If the field moisture content
of the soil is higher than the OMC, it may be necessary to
delay the construction until the soil dries to the level of
desired OMC.
 The soil with added water is mixed thoroughly using
appropriate equipment and the mixed soil is spread again
to uniform layer thickness.
 The soil layer is compacted by rolling using the selected
equipment so as to obtain the specified MDD.

20. CONSTRUCTION OF SUBGRADE
 The subgrade is constructed using superior soils of
specified properties brought from selected borrow pits.
Materials like selected soil, moorum, gravel and a mixture
of these free from organic matter are considered suitable
construction of subgrade.
 Construction method :
 The selected soil in loose condition is spread to the required
grade and cross slope (camber) in layers of desired
thickness using appropriate equipment such as blade
grader, over the prepared surface (i.e. Top of the
embankment or top of the embankment)

21. CONSTRUCTION OF SUBGRADE
 Additional quantity of water as required is sprayed over the
soil so as to obtain the OMC of the soil determined from the
laboratory compaction test.
 The soil with added water is mixed thoroughly using
appropriate equipment and the mixed soil is spread again
to uniform layer thickness, grade and cross slope.
 The soil layer is compacted by rolling using the selected
equipment so as to obtain the specified MDD.
 After ensuring that the layer has been compacted to the
desired density, the next layer of soil is sprayed over this,
water added, mixed and compacted. The process is
repeated until the desired compaction thickness is achieved

22. SOIL STABILIZATION
 The term soil stabilization means the improvement of the
stability or bearing power of the soil by the use of
controlled compaction, proportioning and/or the addition
of suitable admixtures.
 Necessity of soil stabilization :
 To increase the bearing capacity (stability) of soil.
 To reduce the cost of construction.
 To modify chemical properties of soil.
 To increase the shear strength of soil.
 To increase the flexibility of soil.

23. CONSTRUCTION OF GRANULAR SUB-
BASE/DRAINAGE LAYER
 The granular sub-base (GSB) course is provided between
the sub grade and the base course of all highway
pavements, in one or more layers.
 The GSB layer should be laid over the full width of the
prepared sub grade, extending up to the side drains so as to
serve as a ‘drainage layer’ of the pavements, if separate
drainage layer is not provided.

24. CONSTRUCTION OF GRANULAR BASE
COURSE - WBM
 Water bound macadam (WBM) shall consists of clean,
crushed course aggregates mechanically interlocked by
rolling, and voids filled with screening and binding material
with the assistance of water, laid on a prepared sub grade,
sub-base, base or existing pavement as the case may be.
 WBM may be used as a sub base, base course or surfacing
course depending upon category of road.
 The WBM shall not be laid on an existing bituminous top
surface without scarifying or providing adequate measures
for proper bond and drainage at the interface of existing
bituminous surface and WBM layer.

25. CONSTRUCTION OF GRANULAR BASE
COURSE – WMM
 Wet Mix Macadam (WMM) construction is an
improvement upon the conventional WBM , as the base
course.
 The WMM consists of well graded crushed aggregates and
granular material like graded coarse sand are mixed with
water and rolled to a dense mass on a prepared surface of
sub-base course.
 The thickness of each compacted layer shall not be less than
75 m and not more than 250 mm.

26. CONSTRUCTION OF BITUMINOUS
PAVEMENT LAYERS
 Bituminous pavement layers from an important part of the
flexible pavement layer system.
 Different types of bituminous layers are being used as
surface course of flexible pavements. Thin bituminous
surfacing is provided on roads with light traffic loads,
thicker bituminous layers are required to withstand heavy
traffic loads.
 In case of heavy traffic roads, additional bituminous
pavement layers in the form of “binder course” is provided
before laying the bituminous surface course.

27. CONSTRUCTION OF BITUMINOUS
PAVEMENT LAYERS
 Prime Coat :
 Prime coat is an application of low viscous liquid
bituminous material over an existing porous or absorbent
pavement surface like WBM.
 Tack Coat :
 Tack coat is a very light application of asphalt, usually
asphalt emulsion diluted with water. It provides proper
bonding between two layer of binder course. It is generally
applied on impervious surface.

28. DIFFERENT TYPES OF CEMENT
CONCRETE PAVEMENTS
 Different types of cement concrete (CC) pavements are :
 Plain concrete pavements
 Reinforced concrete pavements
 Continuously reinforced concrete pavements with elastic
joints
 Fibre reinforced concrete pavements

29. DIFFERENT TYPES OF CEMENT
CONCRETE PAVEMENTS
 Plain concrete pavements :
 Because of their cost- effectiveness and reliability, the vast
majority of concrete pavements constructed today are
Jointed Plain Concrete Pavement (JPCP) designs.
 They do not contain reinforcement. They have transverse
joints generally spaced less than 5 to 6.5 m (15 to 20 ft)
apart and longitudinal joints. They main contain dowel bars
across the transverse joints (expansion joints and
construction joints) to transfer traffic loads across slabs and
may contain tie bars across longitudinal joints to promote
aggregate interlock between slabs.

30. DIFFERENT TYPES OF CEMENT
CONCRETE PAVEMENTS
 Reinforced concrete pavements :
 Reinforced cement concrete (RCC) pavement slabs are
constructed on some road stretches that are subjected to
the following types of adverse conditions :
 Very heavy traffic loading
 Poor soil conditions
 Poor drainage
 Extreme climatic conditions
 As the reinforcement is generally placed at about the mid
depth of the slab or a little above the mid depth, the
reinforcement may not play a significant role.

31. DIFFERENT TYPES OF CEMENT
CONCRETE PAVEMENTS
 Continuously reinforced concrete pavements with
elastic joints :
 CRCP-EJ designs contain a significant amount of
longitudinal reinforcement, typically 0.33 to 0.40 percent
of the cross-sectional area.
 The longitudinal steel is given a thick coating of bitumen
for a total length of 1.5 m near the joints (0.75 m on either
side of joint) in order to prevent the bond with the concrete
near the joints. These joints are called “elastic joints”.
 25 percent of longitudinal steel is provided as transverse
steel.

32. DIFFERENT TYPES OF CEMENT
CONCRETE PAVEMENTS
 Fibre reinforced concrete pavements :
 FRCs are advantageous in many applications. In simple
cost comparison with concrete without fibres, FRC may
appear to be costly in the beginning.
 FRC with higher flexural strength, shear strength,
toughness, fatigue endurance and better post crack
behaviour, is needed for concrete pavements, runways,
bridge decks, wearing coast etc.
 FRC has been used to provide durable concrete pavements
with improved cracking resistance and reduction in the
required slab thickness.

33. COMPONENTS OF CEMENT CONCRETE
PAVEMENT AND ITS FUNCTIONS
 The components of cement concrete pavement
structure of major highways catering for heavy
traffic loads are as under :
 Soil subgrade
 Drainage layer
 Sub base course made of Dry Lean Concrete (DLC)
 Separation membrane laid on the top of the concrete sub
base course
 CC pavement slab using “Paving Quality Concrete” (PQC)
 Construction of different types of joints

34. COMPONENTS OF CEMENT CONCRETE
PAVEMENT AND ITS FUNCTIONS
 Soil subgrade :
 The subgrade is constructed using superior soils of
specified properties brought from selected borrow pits.
 Materials like soil, moorum, gravel and a mixture of these
free from organic matter are considered suitable
constructed of subgrade.
 The maximum permissible size of coarse material / stone
aggregate for the construction of subgrade is 50 mm.

35. COMPONENTS OF CEMENT CONCRETE
PAVEMENT AND ITS FUNCTIONS
 Drainage layer :
 The performance and service life of the CC pavements
depends to a great extent on the effective functioning of the
drainage layer during the 30 years design life period.
 Well designed and constructed crushed aggregate drainage
layer of thickness 200 mm to 300 mm with a permeability
not less than 30 m per day is desirable.
 A geo-filter may be laid between the subgrade and the
granular drainage layer to provide a longer service life to
the drainage layer.

36. COMPONENTS OF CEMENT CONCRETE
PAVEMENT AND ITS FUNCTIONS
 Sub base course made of Dry Lean Concrete(DLC) :
 On important highways with heavy traffic, generally a sub
base coarse consisting of “Dry Lean Concrete” (DLC) is laid
between the drainage layer and the CC pavement slab.
 By providing an effective drainage layer and DLC layer, it is
possible to prevent the early failure of the rigid pavement
due to “pumping and blowing” consequently the effective
service life of the CC pavement is also substantially
increased.

37. JOINTS IN CEMENT CONCRETE
PAVEMENT
 Types of joints in cement concrete pavement are :
 Expansion joints
 Contraction joints
 Warping joints
 Construction joints

38. JOINTS IN CEMENT CONCRETE
PAVEMENT
 Expansion joints :
 These are provided to allow for expansion of the slabs due
to rise in slab temperature above the construction
temperature of the cement concrete.
 Expansion joints also permit the contraction of slabs.
 Expansion joints in India are provided at interval of 50 to
60 m for smooth interface laid in winter and 90 to 120 m
for smooth interface laid in summer.

39. JOINTS IN CEMENT CONCRETE
PAVEMENT
 Contraction joints :
 Construction joints are provided to permit the contraction
of the slab, due to fall in temperature. This joints are spaced
closer than expansion joints.
 Load transfer at the joints is provided through the physical
interlocking by the aggregates projecting out of the joint
faces. As per IRC specification the maximum spacing of
contraction joints in unreinforced CC slabs is 4.5 m and in
reinforced slab thickness is 14 m.

40. JOINTS IN CEMENT CONCRETE
PAVEMENT
 Warping joints :
 The warping joints are provided to relive the warping stress
developed in the pavement in order to permit free warping
in the longitudinal direction, the transverse warping joints
of the weakened plane may be suitably provided.
 These are also known as hinged joints.

41. JOINTS IN CEMENT CONCRETE
PAVEMENT
 Construction joints :
 When the placing of concrete is suspended at the end of day
or for more than 30 minutes, it becomes necessary to
provide construction joints.
 It is thus clear that there will be no necessity of the
construction joints, if the work is discontinued at
transverse, expansion or contraction joints with the
advanced planning.

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