Hydrodynamic pressure distribution in saturated void beneath cement concrete pavement slab

Abstract

ABSTRACT The void beneath cement concrete pavement slab (CCPS) is one of the common defects, which can cause the pavement cracking when heavy vehicle load is exerted on the pavement. The void expands when the water trapped inside erodes the inner surfaces of void circularly, bringing more cracks easily. Due to the close relationship with the erosion of the void, the hydrodynamic pressure distribution in saturated void beneath CCPS is investigated in this paper. Firstly, a theoretical expression of the hydrodynamic pressure in saturated void is proposed taking in account the law of mass conservation and the theorem of momentum. Secondly, the deformation patterns of the CCPS and the fluid-structure interaction (FSI) are discussed based on the proposed method. The results show that the hydrodynamic pressure and the water flow velocity in the void are overvalued while the rigid deformation pattern of CCPS is employed and the FSI is ignored. Finally, some influence factors are discussed. It is obtained that, both the maximum hydrodynamic pressure and the average velocity of water increase with the increase of the load amplitude, the vehicle speed and the void dimension. The conclusions are helpful for the prevention and maintenance of void beneath the CCPS.