Dynamic response of pile group in two-layered soils under scour condition by FEM-ALEM approach

Abstract

Pile groups for the bridge and jacket foundations in the marine or traffic geotechnical engineering are significantly influenced by the current scour in service. Under the effects of scour and dynamic load, the capability of the pile foundations to resist deformation is reduced and thus causes structural failure. This paper presents a FEM-ALEM coupling approach to study the dynamic interaction between a pile group and layered soils under scour condition. Behaviors of the pile group are analyzed by applying the finite element method. Fundamental solutions of the layered soils under scour condition are obtained by adopting the analytical layer element method. Comparisons with existing solutions are performed to confirm the correctness of the present approach, and numerical examples are provided to discuss the effects of the scour type, scour depth, scour width and layered property of soil on the dynamic behaviors of the pile group. The present coupling approach can be used to evaluate the responses of a pile group embedded in layered saturated soils under scour due to a vertical dynamic load.