摘要
为了减少动态时程法的计算开销,根据地震时程记录的能量在时间-频率域内主要集中在特定时间段和低频分量中的特点,用离散小波变换,变采样率重构时程记录,以达到在时程计算时减少积分步数,节约计算时间的目的。通过有限元数值实验,表明该法可有效缩短计算时间,同时计算误差不超过5%,在工程范围内可以接受。
Time-frequency joint method is used to analyze the energy distribution of seismic time history in time-frequency domain.Since the main part of the energy is located in low frequency component and specific time,the time history is reconstructed by low sampling rate in certain time,and the calculation burden is reduced.Numerical experiment results show that the approach is effective and the deviation caused by it is no more than 5 percent,which is acceptable to engineering application.
引文
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