Amplification pattern of 2D semi‐sine‐shaped valleys subjected to vertically propagating incident waves

Abstract

Abstract This paper presents the preliminary results of an extensive numerical parametric study on seismic behaviour of two‐dimensional semi‐sine‐shaped valleys subjected to vertically propagating incident in‐plane compression and shear waves. The medium is assumed to have a linear elastic constitutive behaviour. All calculations are executed in time‐domain using the direct boundary element method. Clear perspectives of the amplification patterns of the valley are presented by investigation of the frequency‐domain responses. It is shown that wavelength, site geometry and in a less order of importance, wave type and material parameters, are the independent key parameters governing the valley's amplification pattern. Some simple rules are obtained which could be used in seismic microzonation and seismic design of structures founded inside the valley. Copyright © 2006 John Wiley & Sons, Ltd.