多点地震动激励下的高效反应谱方法

An efficient seismic response spectrum method under multi-support excitations

在多点地震动激励下,结构的反应谱分析计算非常耗时。结构的地震谱响应可以用若干个相关系数来表示,如果相关系数使用解析形式来表示,可以大大减少计算时间。本文提出了空间相干函数的近似表达式,并对其系数进行积分,得到了相关系数的解析式。该解析表达式根据克拉夫-彭津(Clough-Penzien)和胡聿贤自功率谱密度函数模型推导得出。案例桥梁的计算结果表明,相关系数的近似解析表达式具有足够的工程精度,用于多点地震反应谱计算具有极高的效率。

The seismic response spectrum analysis of structures is time-consuming under multisupport excitations. The seismic spectral response of structures can be expressed based on several correlation coefficients and the time consumption can be greatly reduced if the coefficients are expressed in closed-form. In this paper, approximate expressions of spatial coherence functions are suggested. Then integrals for the coefficients are carried out analytically and their closed-form expressions are obtained. The closed-form expressions are developed from CloughPenzien’s auto-power spectral density and Hu’s APSD. The numerical results show that the approximate closed-form expressions of correlation coefficients are of enough engineering accuracy and high efficiency for response spectrum method under multi-support excitations.