VI. RESEARCH WORK DONE IN ACADEMIC INSTITUTIONS RELATED TO THESIS WORK

B. PAVEMENT ENGINEERING AND PAVING MATERIALS
12. Finite Element Analysis of Concrete Pavements with Cut-outs
Date of Start

May 2005
Indian Institute of Technology, Kharagpur (S,I)

 

Scope and Objectives

Analysis of concrete pavement using Finite Element Method to study the effects of cut-outs, load transfer by aggregate interlock and dowel bar system and also top down cracking due to wheel load and thermal effect.

 
Methodology
Three-dimensional Finite Element Analysis was carried out for modeling concrete pavement using the structural analysis software ANSYS.
 
Findings and Conclusions
(i) It was found that the flexural tensile stresses were significantly higher for pavements with cut-out than without cut-out. Limit state method of design was adopted for the reinforcement to account for the flexural tensile stresses due to cut-out portion.

(ii) It was found that tied concrete shoulder reduces the stresses in the main pavement considerably and the magnitude of load transfer depends on the modulus of aggregate interlocking and subgrade modulus.

(iii) It was observed that the modulus of aggregate interlocking is the basic index of load transfer capacity at the joints.

(iv) In the present analysis, graphs were given for the modulus of dowel support v/s joint load transfer efficiency for different thickness of concrete slab and modulus of subgrade reaction. By conducting FWD test, the joint load transfer efficiency can be known; therefore the modulus of dowel support can be back calculated.

(v) Because of the warping stresses the slab becomes concave upward and when a vehicle passes over such slab may cause top down cracking. It was found that if the pavement having high intensity of heavy axle loads, top down cracking cannot be ruled out and fatigue damage must be computed for such cases also.