PARAMETER DETERMINATION OF BOUC-WEN HYSTERESIS MODEL FOR LEAD RUBBER BEARING

This study develops a hysteresis model for lead rubber bearings (LRBs) using Bouc-Wen (BW) model and particle swarm optimization (PSO). Bilinear model often overestimate response acceleration, whereas BW model offers more accurate nonlinear hysteresis behavior. Static cyclic loading tests on LRB specimens validated the model. Parameters of BW model were optimized via PSO, and a simplified parameter determination method was proposed. Key parameters such as initial stiffness, secondary stiffness, and yield displacement can be accurately driven by existing formula, while parameters related to unloading stiffness and stiffness transition are newly proposed in this study.