Abstract
White topping structure（WTS）is proposed as one of repair methods of rutted asphalt pavement. White topping method removes the upper part of surface of existing asphalt pavement by about 10cm, and overlays the remaining asphalt layer with thin concrete slabs. In this method, relatively short joint spacing is employed to reduce the thermal stress in the concrete slabs.
In WTS, bonding between the concrete slab and the remaining asphalt layer. The current design method is not able to deal with WTS, because there is no proper structural model to represent both thin concrete slabs on asphalt layer. This study employed three dimensional finite element method（3DFEM）combined with the concept of equivalent elastic modulus of asphalt layer（stiffness）. Based on the simulations with the method, the effects of joint layout of concrete slab, stiffness of asphalt layer, interface condition, thermal condition, and cracking in asphalt layer on the mechanical behavior of WTS were investigated.
It was found that the stiffness of asphalt layer has more significant effect on the behavior of WTS than joint layout. Too low stiffness of asphalt layer increase the possibility of separating the bonding between unloaded concrete slab and underneath asphalt layer at the interface. Also, too short joint spacing, however, results in the large strains in asphalt layer.
