考虑岩土介质随机特性的工程场地地震动随机场分析

The analysis of coherency function of earthquake ground motion considering stochastic effect in site media

将随机结构正交展开理论和随机振动分析的虚拟激励原理运用于场地波动有限元分析,形成了一种可以考虑岩土介质随机特性对工程场地地震动相干函数影响的分析方法。实例分析表明,场地介质随机特性将在场地卓越频率附近显著降低迟滞相干函数值,在进行工程场地地震动随机场研究时应当考虑场地介质随机特性的影响。

With the introduction of the orthogonal expansion method and the pseudoexcitation method into the wave finite element analysis of complex site, a method with which the effect of the random site media on the coherency function of earthquake ground motion can be considered is proposed in this paper. The numerical examples show that the stochastic media of the site tends to reduce the lagged coherency function in the vicinity of the predominant frequency. This diminution phenomena resulted from the random site media should be considered in the coherency function research.