基于Bouc-Wen模型橡胶隔震支座的非线性特性识别

Nonlinear characteristics identification of rubber isolation bearing base on Bouc-Wen model

基于简化的Bouc-Wen迟滞模型来描述隔震支座非线性力学模型,为基础隔震结构在地震作用下的隔震支座提供合理的力学性能状态评估,提出判断隔震支座进入非线性阶段时域演化特征的小波系数能量比指标;并采用小波多分辨分析理论进行隔震支座的非线性特性及参数识别.数值算例表明,小波系数能量比可以很好地判断基础隔震结构在不同地震激励水平下的非线性状态,利用小波多分辨识别算法可以准确识别隔震结构隔震层的非线性特性及模型参数.

Nonlinear mechanical model of isolation bearing was described based on simplified Bouc-Wen hysteresis model. In order to provide a reasonable state assessment of mechanical properties of isolation bearing in base isolation structure under seismic excitation, an index of wavelet coefficient energy ratio was proposed to discriminate the time-domain evolution characteristics of the isolation bearing entering into nonlinear phase and, identify the nonlinear characteristics and parameters of the isolation bearing with wavelet multi-resolution analysis theory. Numerical computation example shows that the wavelet coefficient energy ratio can be employed to carry out a fine detection of nonlinear state of the isolation bearing at various seismic excitation levels and the nonlinear characteristics and model parameters of the base isolation structure can be accurately identified by using the wavelet multi-resolution identification algorithm.