Identification of parameters in the model of rubber bearing by using sequential non-linear least-square estimation

Due to the complex nature of the excitation and the inherent dynamics characteristics of restoring force of the base isolation system, the response of rubber bearings subject to strong earthquake are very complicate. Hence it is necessary to describe the restoring force and evaluate the condition of the rubber bearings while they are running. In this paper, the simplied Wen's model is put forward for analyzing the properties of rubber bearing. Based on vibration data measured from sensors, a new data analysis method, referred to as the sequential non-linear least-square estimation (SNLSE), has been used. This approach has significant advantages over the extended Kalman filter (EKF) approach in terms of the stability and convergence of the solution as well as the computational efforts involved. The accuracy and effectiveness of the new approach has been demonstrated using a kind of rubber bearing (GZN110). This research results can not only be taken as a useful reference for the rubber bearings' seismic designing, but also provide related theory for the rubber bearings' health monitoring.