大規模断層破壊による地震動の推定

Abstract

Prediction model of near-source ground motions for great earthquakes is proposed basedon the statistical prediction model of nonstationary earthquake motions. The synthetic numberNG of evolutionary power spectrum to estimate large earthquake ground motions is obtained in theform of a linear relation between NG and the logarithmic value of seismic moment Mo using 48accelerograms from 8 earthquakes recorded in Japan.Fault model for prediction of near-source ground motions, which includes seismic moment, areaof fault, rupture direction, and rupture velocity, is proposed. Validity of the model is examinednot only for peak acceleration and cumulative acceleration power but for pseudo velocity responsespectra. The model is applied for estimation of ground motions caused by the hypothetical TokaiEarthquake (M=8.O).