Pavement design is the process of developing the most economical combination of pavement layers (in relation to both thickness and type of materials) to suit the soil foundation and the traffic to be carried during the design life.

1. SUBMITTED BY:-
KAMAL KISHOR PATEL
GUIDED BY:-

2. PAVEMENT
The pavement is the structure which separates
the tyres of vehicles from the underlying
foundation material. The later is generally the
soil but it may be structural concrete or a steel
bridge deck.

3. TYPES OF PAVEMENT
Flexible
Pavements
Rigid
Pavements

4. RIGID PAVEMENTS
 Thus in contrast with flexible pavements the
depressions which occur beneath the rigid
pavement are not reflected in their running
surfaces.
 In rigid pavements the stress is transmitted to the
sub-grade through beam/slab effect. Rigid
pavements contains sufficient beam strength to be
able to bridge over localized sub-grade failures and
areas of inadequate support.

5. FLEXIBLE PAVEMENTS
Flexible Pavements are constructed from bituminous
or unbound material and the stress is transmitted to
the sub-grade through the lateral distribution of the
applied load with depth.

6. Natural Soil (Subgrade)
Aggregate Subbase Course
Aggregate Base CourseAsphalt Concrete

7. Wheel Load
Sub-grade
Bituminous Layer
Typical Load Distribution in Flexible Pavement

8. PRINCIPLES OF PAVEMENT DESIGN
 The tensile and compressive stresses induced in a
pavement by heavy wheel loads decrease with
increasing depth. This permits the use, particularly in
flexible pavements, of a gradation of materials,
relatively strong and expensive materials being used
for the surfacing and less strong and cheaper ones for
base and sub-base.
Pavement design is the process of developing the
most economical combination of pavement layers
(in relation to both thickness and type of materials)
to suit the soil foundation and the traffic to be
carried during the design life.

9. DESIGN LIFE
The concept of design life has to be introduced to ensure that a
new road will carry the volume of traffic associated with that
life without deteriorating to the point where reconstruction or
major structural repair is necessary. For roads in Britain the
currently recommended design is 20 years for flexible
pavements.

10. Name of site – NH-30 MMI – SADANI DARBAR.
Year of starting flexible pavements in this form:- 2014-15
Total length = 10 km.
Total width = 24.40 m.

11. 1.SOIL FAN.
2.SOIL COMPACTOR.
3.VIBRATOR ROLER.
4.TAR BOILER.
5.PAVER MACHINE.

13. SOIL COMPACTOR

14. VIBRATOR ROLLER

15. PAVER MACHINE

16. PERFORMANCE AND FAILURE CRITERIA
A road should be designed and constructed to provide
a riding quality acceptable for both private cars and
commercial vehicles and must perform the functions
i.e. functional and structural, during the design life.

17. Failure Mechanism (Fatigue and Rut)
Bitumen Layer
Unbound Layer
Nearside Wheel Track
Fatigue Crack
Rut Depth

18. ASPECTS OF DESIGN
Functional Structural
Safety Riding Quality
Can sustain
Traffic Load

19. Structural Performance
Strength
Safety
Comfort
Functional Performance

20. RUDIMENTARY DEFINITION
Pavement Thickness Design is the determination of required
thickness of various pavement layers to protect a given soil
condition for a given wheel load.
Given Wheel Load
150 Psi
3 Psi
Given In Situ Soil Conditions
Asphalt Concrete Thickness?
Base Course Thickness?
Subbase Course Thickness?

21. PAVEMENT DESIGN PROCESS
Climate/Environment
Load Magnitude
Volume
Traffic
Material
Properties
Asphalt Concrete
Roadbed Soil (Subgrade)
Base
Subase

22. • Pavement Design Life = Selected
• Structural/Functional Performance = Desired
• Design Traffic = Predicted
?
Asphalt Concrete Thickness ?
Base Course Thickness ?
Sub-base Course Thickness ?
Truck

23. WHAT DO WE MEAN BY ?
PREDICTED DESIGN TRAFFIC

24. Traffic Loads Characterization
Pavement Thickness Design Are Developed
To Account For The Entire
Spectrum Of Traffic Loads
Cars Pickups Buses Trucks Trailers

25. AXLE LOAD & RELATIVE DAMAGE
1.0
1.1
2.3
3.3
4.7
6.5
8.7
11.5
14.9
18.9
23.8
29.5
36.3
44.1
53.1
63.4
75.2
0
10
20
30
40
50
60
70
80
DAMAGEPERPASS
8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
SINGLE AXLE LOAD (Tons)

26. 1. Adaptability to stage construction
2. Availability of low cost types that can be easily built.
3. Ability to be easily opened & patched.
4. Easy to repair frost heave & settlement.
5. Resistance to the information of ice glaze.

27. 1.Higher maintenance costs.
2.Shorter life span under heavy use.
3.Damage by oils and certain chemicals.
4.Weak edges that may require curbs or edge devices.

28. 1.The positive effects of geo grid reinforced base course
can economically & ecologically be utilized to reduce
reinforced aggregate thickness.
2.The design engineer should be well aware of possible
problems and should use this relative new tool for solving
them.
3.For this he should understand properties and capabilities
of the geo grid material at hand.