An Investigation on Load Transfer Behaviour for Whitetopping Pavements

The present work investigates the influence of overlay thickness, bituminous layer thickness, its elastic modulus and bonding condition on flexural stress and load transfer efficiency (LTE) of aggregate interlocked joints in Whitetopping. Analysis has been carried out by developing a three-dimensional finite element model of Whitetopping. The results indicate that overlay thickness has a significant influence on flexural stress and LTE of joints. The flexural stress decreases by 67% and LTE increases by 7% when the overlay thickness is increased from 100 to 200 mm. The influence of bonding condition on flexural stress and LTE is however, found to be more pronounced for lower overlay thickness. The stiffness of bituminous layer influences the flexural stress and load transfer, which is more prominent for thinner concrete overlay than a thicker one. For 100 mm overlay thickness, the flexural stress increases by 27%, when the elastic modulus of bituminous layer decreases from 2500 to 750 MPa for bonded interface whereas, it is 11% for unbonded condition. For 100 mm overlay thickness, the LTE varies from 83% to 87% for similar variation of bituminous modulus, whereas for 200 mm overlay thickness, the LTE remains almost the same for all bituminous modulus values.