Scattering and diffraction of earthquake motions in irregular elastic layers, I: Love and SH waves

Abstract

We describe the wave propagation through an irregularly layered, elastic medium for incoming body (SH) and surface (Love) waves. As a result of irregular geometry, each layer generates additional waves by scattering and diffraction. These additional waves modify the input motions and locally may lead to larger motions and concentrations of stresses, strains, and rotations on or below the ground surface. For engineering design, and in particular for analyses of soil-structure interaction, it is important to understand the nature and the consequences of such motions.The scattering and diffraction of Love and SH waves by irregular layers will be investigated by the weighted-residuals method. The scattered and diffracted mode shapes and spectral amplification characteristics at different frequencies will be examined and discussed.