基于振动响应的隔震支座的非线性建模及参数估计

为了研究隔震橡胶支座的力学特性,采用修正的Wen模型分析隔震支座的非线性动力行为,并用试验方法测试得到了该模型的相关参数.鉴于该模型具有高度的非线性,传统的参数识别方法不再适用,本文根据非线性系统状态参数估计理论,利用多项式一阶近似技术来代替EKF滤波技术中的求导线性化过程,估计迟滞模型的非线性参数.该方法具有运算简单、计算精度高、易于实现的优点.通过进行两种简谐激励下的仿真和试验,结果表明隔震支座的模型参数的递推结果相当可靠,从而证实了该方法在隔震支座检测和健康状态评估中的有效性.

MODELING OF A RUBBER BEARING AND ITS PARAMETERS ESTIMATION BASED ON ITS DYNAMIC RESPONSE

Due to complex nature of excitations and the inherent dynamic characteristics of restoring force of a base isolation system,the response of a rubber bearing subject to strong earthquake is very complicated.Hence it is necessary to describe the restoring force and evaluate the behavior of the rubber bearing while it is working.Here,the revised Wen's model is put forward for analyzing the properties of a rubber bearing.Since the high-nonlinearly hysteretic model can't be identified by the extended Kalman filter approach,the parameter values are estimated by the first-order polynomial approximation method on the basis of the actual acceleration records.The method proposed has some virtues,such as,less computation,high precision,and easy to realize.The studying results can not only be taken as a useful reference for the seismic design of rubber bearings,but also provide the theoretical base for structural health monitoring(SHM) of rubber bearings.