地震動に含まれる位相特性のモデル化

Abstract

Modeling of phase charactristics of a seismic moion is an important subject tosynthsize a realistic seismic ground motion. We have developed simple methods toextract the essential phase characteristics of seismic motion. Deconvoluting aseismic motion into the minimum phase shift function and all-pass function, thephase spectra of both functions are calculated. Using smoothing technique the basiccharactristics of both phase spectras are investigated and a method reconstructingoriginal phase spectra is proposed based on the probabilistic consept. The cepsrumanalysis is also applied to deconvolute an obsered seisimic wave into a train ofimpulses and a system transfer function. Phase spectra of these functions aremodeled in a simple manner.