DESIGN OF RIGID PAVEMENT:A CASE STUDY

Under the guidance ofDr. S.B. Vanakudre

ProfessorDepartment of Civil Engineering

 Submitted By:

Abhijeet Kumar Singh 2SD11CV001 Aquib Nasir Razi 2SD11CV009 Dibyajyoti Sarma 2SD11CV020 Kamlesh Kumar 2SD11CV031

CONTENTS1. INTRODUCTION2. TYPES OF RIGID PAVEMENT3. OBJECTIVE4. DESIGN FACTORS5. CHARACTERISTICS OF SUBGRADE AND SUB-BASE6. CALCULATION OF CBR7. DESIGN CALCULATIONS8. AUTOCAD DESIGN9. REFERENCES

• Rigid pavements are those which possess noteworthy flexural strength and rigidity.

• The critical condition of stress in the rigid pavement is the maximum flexural stress occurring in the slab due to wheel load and temperature change.

• Rigid pavements are made of Portland cement concrete-either plain, reinforced or pre-stressed concrete

INTRODUCTION

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.

TYPES OF RIGID PAVEMENT

Three types of concrete pavements are commonly used, namely:•Jointed plain concrete pavement (JPCP)•Continuously reinforced concrete pavements (CRCP)•Jointed reinforced concrete pavement (JRCP)

Jointed Plain Concrete Pavement (JCPC)

Continuously Reinforced Concrete Pavement (CRCP)

Jointed Reinforced Concrete Pavement (JRCP)

OBJECTIVETo design the pavement for Navalgund bus stand

DESIGN FACTORSPavement 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

FACTORS GOVERNING DESIGN:•Wheel load•Design Period•Design Traffic•Temperature Differential•Characteristics of subgrade and sub-base•Characteristics of concrete

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 )

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

PROCEDURE:CBR.docx

CALCULATION OF K VALUE

DESIGN CALCULATIONS.docx

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

AUTOCAD DESIGN OF PAVEMENTS

FINAL.dwg

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”