Seismic response of pile groups under oblique‐shear and Rayleigh waves

Abstract A simple analytical solution is presented to calculate the pile‐soil‐pile interaction and eventually the dynamic response of pile groups when excited by the passage of Rayleigh waves and obliquely incident SH‐waves. A dynamic Winkler model, with realistic frequency‐dependent ‘springs’ and ‘dashpots’ in conjunction with physically motivated approximations is utilized to compute the wave field radiating from an oscillating pile and the effect of this field on an adjacent pile. The coupled rocking motion of the pile group resulting from Rayleigh waves and the torsional motion of the pile group resulting from SH‐waves is accurately predicted by a simple mathematical expression. The results of the presented method can be obtained with ‘hand calculations’ and are in excellent agreement with results from ‘rigorous’ solutions based on integral equation formulations. It is found that the group response is primarily affected from the phase difference of the input seismic motion at the location of each pile (wave‐passage effect). Pile‐soil‐pile interaction has insignificant effect and can be neglected.