Coupled simulation of wave propagation and water pumping phenomenon in driven concrete piles

The purpose of the paper is to simulate the water pumping phenomenon that may cause damage to driven concrete pile below water. The cracked concrete is modeled as water saturated porous media, where the cracked region is given a high permeability. A FE program based on a coupled hydro-mechanical theory has been developed to perform simulations. The simulations clearly demonstrate the water pumping phenomenon, where water is pressed out from the crack by the compressive wave induced by the pile driving hammer, and then sucked back again by the following tensile wave. Further, the principal tensile stress distribution indicates that further cracking is likely to occur at the surface of the pile around the crack, which is in agreement with the damages seen on piles in reality.