Practical technique for analysing free-field response of horizontally layered viscoelastic half-space excited by vertically travelling seismic waves

Abstract

A practical technique for directly calculating the response of a viscoelastic layered half-space excited by vertically travelling seismic waves in the time domain was developed. Based on the relationship between the superposition of the upward and downward waves incident on the soil interface and the superposition of the upward and downward waves emitted from the interface, the governing equations were derived to prevent the cumbersome recording and synthesis of the upward and downward waves. In addition, a technique to decompose seismic waves was applied to precisely model the hysteretic damping of soil in the time domain. The proposed method is simple, practical, and easy to implement in programs, and it is an alternative approach for computing the response of the viscoelastic layered half-space. Several examples, including the viscoelastic layered half-space response generated by incident harmonic and seismic waves, are presented to demonstrate the preciseness and versatility of the proposed method.