多点输入下场地非线性地震反应分析计算模型

为考虑强震下土层反应的非线性及地震波的空间变化特性，基于直接迭代法和逐步积分法提出多点输入非线性分析的一种增量迭代格式，从而建立土层多点输入地震反应非线性分析方法。同时，为降低多点输入非线性分析近代过程中刚度矩阵的求逆次数，对原迭代方法作进一步推导，提出采用试管因子的试算迭代法，在不降低计算精度的基础上，有效地减少计算时间，编制了可进行一致输入、多点输入的非线性和等价线性化分析的有限元程序，计算结果表明，对于重大结构有进行多点输入地震反应分析的必要。

Computational Model for Nonlinear Seismic Response Analysis of Soil Site under Multi-support Excitations

In order to consider the nonlinear characteristics of soil site and the spatial variation of ground motion,the incremental iterative scheme for nonlinear analysis of soil site seismic response under multi support excitations is developed,based direct iteration method and step by step time integration scheme.In order to decrease the times of evaluation inverse for nonlinear seismic response analysis under multi support excitations,the trial and error iteration method is developed by a trial factor.It can reduce the computational time effectively.According to the proposed computational model,a computer program is worked out.It can perform the nonlinear or equivalent linearization analysis of seismic response under uniform or multi support excitations.The results show that the seismic response analysis under multi support excitations is necessary for large scale structures.