基于不同参数的基础隔震结构非线性概率密度演化

为了研究不同设计参数条件下基础隔震结构非线性响应的概率密度演化特征，采用两质点模型来模拟基础隔震结构，隔震层与上部结构分别采用Bouc-Wen模型与刚度退化的Bouc-Wen模型来描述其非线性特征，运用概率密度演化理论，进行隔震结构非线性随机地震响应的概率密度演化分析。采用基于物理的随机地震动模型生成人工地震动，提出基础隔震结构非线性随机地震响应的概率密度演化分析的基本步骤。通过改变基础隔震结构的设计参数，同时考虑激励的随机性，研究基础隔震结构非线性随机地震响应的概率密度演化规律。结果表明，基础隔震结构的阻尼比、周期比和屈重比取合理范围，能使隔震结构上部和下部的位移可控。

Analysis of Probability-Density Evolution of Nonlinear Response of Base-isolated Structures Based on Different Parameters

To study the characteristics of the probability-density evolution of the nonlinear responses of base-isolated structures under different design parameters, we used a two-particle model to simulate a base-isolated structure. We then used the Bouc-Wen model and the Bouc-Wen model of stiffness degradation to describe the nonlinear characteristics of the isolation layer and the superstructure, respectively. Based on the probability-density-evolution theory, we analyzed the nonlinear random seismic responses of base-isolated structures. Using a random-ground-motion model to generate artificial ground motion, we propose basic steps for analyzing the probability-density evolution of the nonlinear random seismic response of base-isolated structures. By changing the design parameters of the base-isolated structure and considering the randomness of the excitation, we investigated the probability-density-evolution law of its nonlinear random seismic response. The results show that displacements of base-isolated structures can be controlled if the damping ratio, period ratio, and ratio of yield to weight are in a reasonable range.