Simplified Direct Time Integration Boundary‐Element Method

Abstract

A direct time integration form of the boundary integral method is presented. This method is useful for treating structure‐media interaction problems where the structure is embedded in an infinite medium; problems of this type are often encountered in seismic analysis. The essential new feature of this method is a simplified evaluation of the time convolution integrals which are a standard part of these procedures; the simplification is accomplished by using an exponential approximation to the Green's function. The new procedure saves substantial computer storage and time. The method is applied to a rigid inclusion in a half space subjected to an antiplane wave which propagates horizontally rightward and is a step‐function in time. Results are compared to those obtained by a Fourier synthesis technique and it is shown that the method does not adversely affect the accuracy.