集集地震地震动频谱参数研究

地震动的频谱特征是影响结构动力反应的重要因素。以集集地震动记录为数据基础,对反映地震动频谱特征的4个参数周期(反应谱卓越周期Tp,平滑化反应谱卓越周期To,傅氏幅值谱平均周期Tm和反应谱特征周期Tg)进行了研究。依据理论模型,经非线性回归分析,给出了不同场地上地震动各周期分量随断层距变化的经验公式。结果表明,不同的频谱参数周期反映地震动不同的频谱特征;同一场地上各周期随断层距的增大而增大;To和Tm具有较好的可估性。

Study on the period parameters of ground motions during the Chi-Chi earthquake

The frequency content of earthquake ground motion is very important,because it affects the dynamic response of structural systems.Four scalar parameters(the response spectral predominant period T_p,the smoothed spectral predominant period T_o,the Fourier amplitude spectral mean period T_m,and the characteristic period T_g) those characterize the frequency content of strong ground motion are used to examine the characteristics of ground motions during the 1999 Chi-Chi earthquake.With nonlinear regression analyses,the predictive equations of those periods versus fault distance are established.Results indicate that periods increase with the increasing of fault distance;for the four periods,T_o and T_m can be reliably estimated.