長周期応答スぺクトルの地盤増幅率の経験的予測式とその理論的解釈

抄録

We present a new empirical model to spatially interpolate amplification factors of 5 % damped acceleration response spectra obtained at strong motion stations at intervals of about 10 to 20 km for periods ranging from 0.5 to 10 s. The predictor variable is Tz3.2 which is the propagation time of S wave from the seismic bedrock to the engineering bedrock calculated by velocity structure just beneath the station extracted from three-dimensional model with a grid spacing of about 1km. The logarithm of the amplification factors in the Kanto basin, the Nobi basin, and the Osaka basin are modeled by bi-linear regression lines using the Tz3.2. We also interpret the bi-linear regression lines by medium response of surface waves.