Seismic Response Prediction of Base-Isolated Structures with High-Damping Rubber Bearings

Seismic Response Prediction of Base-Isolated Structures with High-Damping Rubber Bearings

To characterize the highly nonlinear hysteretic behavior of high-damping rubber(HDR) bearings, a previously developed mathematical hysteresis model, rather than the simplified bilinear hysteresis model, is adopted in this study. Unilateral and bilateral seismic simulation tests on a scaled-down multistory structure isolated with HDR bearings under three recorded earthquakes are conducted. Different sets of parameters for the mathematical hysteresis model are identified from the unilateral tests. A feasibility study on applying the identified parameters of the adopted hysteresis model to predict the bilateral seismic responses is performed. Moreover, the applicability of the adopted hysteresis model is investigated through a comparison of experimental measurement and analysis predictions using all sets of identified parameters. The noticeable influence ascribed to different earthquake characteristics such as the effect of near-field and far-field earthquakes on the modeling of HDR bearings is observed. Even though the prediction accuracy of the seismic responses is acceptable in both orthogonally horizontal directions, the bilateral hysteresis modeling of HDR bearings requires further study.