Dynamic non-linear soil-structure interaction analyses of a large diameter pile-supported wharf founded on liquefiable soils.

抄録

This paper investigates the seismic response of a large diameter pile-supported wharf located at the port of Gioia Tauro, in Southern Italy. To capture the non-linear behavior of both the liquefiable ground and the superstructure, fully coupled 2D nonlinear dynamic analyses were conducted with FLAC2D. The cyclic response of the liquefiable soils was modelled using the PM4Sand, while the nonlinear behavior of the piles was accounted for by means of a lumped plasticity model. Hazard-compatible ground motion records were used as input excitations for three different return periods, and two different geotechnical models were developed to capture variable site conditions. The first model represents the native soil deposit, which is comprised of medium to dense coarse-grained soils, while the second model considers the presence of a significantly looser fill that was found in certain areas of the port. Specific attention was given to the estimation of moment and ductility demands on the piles. The sliding mechanism of the submerged slope showed significant variations with ground motion intensity, which in turn yielded different load-transfer patterns on the piles. For long return periods, the in-phase occurrence of kinematic and inertial effects is shown to be more likely at the pile-deck connections, where the kinematic loads are predominant and aggravated by inertial effects during the early stages of ground shaking. Final remarks are given for future studies regarding the assessment of kinematic and inertial effects in pile-supported wharves.