隔震减震主次结构体系非线性随机地震反应分析

为研究隔震、减震装置非线性恢复力特性对2自由度主次结构体系均方根位移反应的影响规律,以隔震、减震装置微分型恢复力模式的滞回参数为变量,地震地面运动模拟成高斯白噪声过程,利用等效线性化方法得到主体结构和二次结构均方根位移反应的表达式.分析表明,主体结构隔震装置非线性恢复力特征对主、次结构的均方根位移反应的影响占主导地位;隔震、减震装置的恢复力特征产生适度非线性有利于减小主、次结构的均方根位移反应.

Nonlinear stochastic earthquake response analysis of primary-secondary systems with base isolation and shock absorption

In order to examine how nonlinear hysteretic restoring force of the devices of base isolation and shock absorption is able to influence the response of root-mean-square displacements for two-degree-of-freedom (2-DOF) primary-secondary systems, hysteretic restoring force of the two devices are expressed by a nonlinear differential equation with several parameters as variables. The earthquake ground motion is simulated as Gaussian white-noise process. The responses of root-mean-square displacements of both primary structure and secondary structure are solved by using the equivalent linearization method.The response statistics by varying parameters indicates that nonlinearity of base-isolation dominates the influence of the response of both primary system and secondry system,and that moderate nonlinearities of the two devices contribute to reduce both response.