Response of Circular Foundation to Spatially Random Ground Motion

Abstract

A method to obtain the response of a rigid circular foundation resting on a uniform elastic half‐space and subjected to a spatially random ground motion is presented. The solution of the resulting mixed boundary‐value problem is based on the use of an integral representation of the response of the foundation in terms of the free‐field ground motion and of the contact tractions between the foundation and the soil obtained in the course of calculating the dynamic compliance functions for the foundation. The results obtained indicate that the effects of the spatial randomness of the ground motion on the response of the foundation are qualitatively similar to deterministic wave passage effects. Both effects involve a reduction of the translational components of the response at high frequencies and the creation of rotational response components.