周波数領域の地盤剛性や地盤柔性を用いた地盤・建屋相互作用系の時刻歴応答解析

抄録

We present five different time-domain substructure approaches which can consider the soil-structure interaction effects efficiently. In the formulations, the soil-structure interaction forces include discrete impulse responses, which are obtained from the frequency domain by transforming the flexibility, mobility, dynamic-stiffness, mechanical impedance and dynamic mass of the unbounded soil, respectively. In order to make the discrete impulse responses causal for step-by-step response analyses, we present a FFT algorithm with causality condition, which only uses the real part or only from the imaginary part of the above mentioned frequency functions. Compared with previous methods, the methods reduce the frequency points to calculate flexibility coefficients, and computational loads in the calculation of time-domain interaction forces. In order to present the validity and accuracy of the present methods, we carry out response analyses of the structure on the layered soil subjected to a strong motion.