This document presents a case study on the design of a rigid pavement for a bus stand in Navalgund. It discusses the different types of rigid pavements and factors considered in the design such as wheel load, traffic, subgrade strength, and concrete properties. It outlines the objectives to design the pavement for the bus stand. The calculations section shows how the California Bearing Ratio was determined for subgrade characterization and the modulus of subgrade reaction was calculated. An AutoCAD drawing of the designed pavement is also included. The references section lists technical manuals and textbooks consulted for the design.
1. DESIGN OF RIGID PAVEMENT:
A CASE STUDY
Under the guidance of
Dr. S.B. Vanakudre
Professor
Department of Civil Engineering
Submitted By:
Abhijeet Kumar Singh 2SD11CV001
Aquib Nasir Razi 2SD11CV009
Dibyajyoti Sarma 2SD11CV020
Kamlesh Kumar 2SD11CV031
4. Properties Flexible Rigid
Design
Principle
Empirical method
Based on load distribution
characteristics of the
components
Designed and analyzed by using the elastic
theory
Material Granular material Made of Cement Concrete either plan,
reinforced or prestressed concrete
Flexural
Strength
Low or negligible flexible
strength
Associated with rigidity or flexural strength
or slab action so the load is distributed over
a wide area of subgrade soil.
Normal
Loading
Elastic deformation Acts as beam or cantilever
Excessive
Loading
Local depression Causes Cracks
Stress Transmits vertical and
compressive stresses to the
lower layers
Tensile Stress and Temperature Increases
Design
Practice
Constructed in number of
layers.
Laid in slabs with steel reinforcement.
Temperature No stress is produced Stress is produced
Force of
Friction
Less. Deformation in the
sub grade is not transferred
to the upper layers.
Friction force is High
Opening to
Traffic
Road can be used for traffic
within 24 hours
Road cannot be used until 14 days of curing
Surfacing Rolling of the surfacing is
needed
Rolling of the surfacing in not needed.
10. DESIGN FACTORS
Pavement design consists of two parts:
•Mix design of materials to be used in each
pavement component layer
•Thickness design of the pavement and the
component layers
11. FACTORS GOVERNING DESIGN:
•Wheel load
•Design Period
•Design Traffic
•Temperature Differential
•Characteristics of subgrade and sub-
base
•Characteristics of concrete
12. CHARACTERISTICS OF SUBGRADE AND SUB-BASE
STRENGTH:
The strength of subgrade is expressed in terms of
modulus of subgrade reaction k, which is defined as
pressure per unit deflection of the foundation as
determined by plate bearing tests.
In case the plate bearing test could not be conducted, the
approximate k- value corresponding to CBR values can be
obtained from its soaked CBR value
using Table 2 (IRC:58-2002 )
13. CALCULATION OF CBR
DEFINITION:
California bearing ratio is the ratio of the force per unit
area required to penetrate in to a soil mass with a standard
circular piston at the rate of 1.25mm/min to that required for
the corresponding penetration of a standard material.
CBR = Test load corresponding to chosen penetration ×100
Standard load for same penetration
17. DESIGN PARAMETERS
•Flexural strength of cement concrete=45kg/cm2
•Effective modulus of subgrade reaction
of the DLC sub-base =30 kg/cm3.
•Elastic modulus of concrete =3×10^5 kg/cm2
•Poisson’s ratio =0.15
•Present traffic=4000 cvpd
•Rate of traffic increase =0.075
•Design life =20 years
20. REFERENCES
• IRC:58-2002,Guidelines for Design of Rigid Pavement
• IRC:15-2002,Standard specifications and code of
practice for construction of concrete roads
• S.K.Khanna and C.E.G Justo –Highway Engineering
• IRC:58-1988,Guidelines for Design of Rigid Pavements
• IRC:37-2001,Guidelines for Design of Flexible
Pavements
• Alam Singh and Chowdhary G.R, “Soil Engineering in
Theory and Practice”
• B.C.Punmia , “Soil Mechanics and Foundations”