Dynamic response of a pile embedded into a layered soil

This paper studies the seismic response of a foundation pile immersed in a saturated coarse-grained deposit. The pile response is examined through a series of three-dimensional dynamic finite element analyses incorporating an advanced plasticity soil model and implementing a fully coupled interaction between the soil skeleton and the pore fluid. The study is mainly focused on the development of the internal forces in a pile immersed into a deposit including two soil layers with a different stiffness, and accounts for the development of excess pore water pressures during the seismic motion. The effects of the initial porosity and of the per-meability of the soil layers are investigated, together with the effects of changing the pile length, the pile diameter, and the boundary condition at the top of the pile. Finally, the results of the finite element simulations are used as a benchmark to evaluate the capability of a num-ber of simplified predictive methods and to provide guidance for their implementation.