非一致激励条件下工程场地地震动相干函数的数值模拟——Ⅰ分析原理和方法

Numerical simulation of coherency function of ground motion under inconsistent excitations: I theories and method

本文将随机振动的虚拟激励原理与工程波动理论散射问题的求解方法相结合,建立了开放系统中非一致激励条件下工程场地地震动随机场的数值模拟方法。该方法将随机输入下的波动分析问题转换为多个虚拟激励下的确定性波动分析组合问题,从而可以方便地获得场地波动观测量之间的谱密度矩阵,进而计算给出工程场地的地震动相干函数。本文还用数值模拟的办法对所提出方法的合理性和稳定性进行了探讨。

Based on pseudo-excitation method and numerical simulation techniques of wave motions about scattering problem, a stochastic wave analysis method is presented in this paper. The inconsistent excitation can be decomposed into a series of irregular incident waves in terms of the spectral decomposition scheme of the Hermitian matrix, with which the coherency function of the ground motions under the inconsistent excitation can be obtained . Numerical results are given to show its stability and rationality.