The concept of base isolation is gaining widespread acceptance in the global earthquake engineering community due to the excellent performance of base-isolated structures during the 1994 Northridge and 1995 Kobe earthquakes. Some of the commonly used isolation systems are elastomeric bearings including lead-rubber bearings (LRB) and high damping rubber (HDR) bearings as well as sliding isolation systems. In recent years, a few mathematical models of high damping elastomeric isolation bearings have been proposed. Hwang et al proposed a mathematical model modified from Pan and Yang’s model. The number of parameters used by Pan and Yang are reduced, and the model is extended to be capable of describing the Mullins effect and scragging effect of high damping rubber bearings.
A mathematical model of high damping elastomeric isolation bearings proposed by Hwang et al has been validated by the cyclic loading test of HDR materials. In this thesis, this model will be validated using cyclic loading tests of HDR bearings. The comparison between the predicted and experimental results indicates the proposed model is capable of predicting the dynamic hysteretic behavior of HDR bearings under different axial loads and different excitation frequencies. In addition, this proposed model of HDR isolation bearings will be used to predict the seismic responses of a base-isolated multistory building tested by a shaking table. A single set of 10 parameters used in the proposed mathematical model is obtained by combined just two hysteresis loop of eight shaking table test. From the test result, it is concluded that the proposed model of HDR isolation bearing is capable of predicting the seismic response of a base-isolated multistory structure if the model is well calibrated by a set of dynamic tests.

The concept of base isolation is gaining widespread acceptance in the global earthquake engineering community due to the excellent performance of base-isolated structures during the 1994 Northridge and 1995 Kobe earthquakes. Some of the commonly used isolation systems are elastomeric bearings including lead-rubber bearings (LRB) and high damping rubber (HDR) bearings as well as sliding isolation systems. In recent years, a few mathematical models of high damping elastomeric isolation bearings have been proposed. Hwang et al proposed a mathematical model modified from Pan and Yang’s model. The number of parameters used by Pan and Yang are reduced, and the model is extended to be capable of describing the Mullins effect and scragging effect of high damping rubber bearings.
A mathematical model of high damping elastomeric isolation bearings proposed by Hwang et al has been validated by the cyclic loading test of HDR materials. In this thesis, this model will be validated using cyclic loading tests of HDR bearings. The comparison between the predicted and experimental results indicates the proposed model is capable of predicting the dynamic hysteretic behavior of HDR bearings under different axial loads and different excitation frequencies. In addition, this proposed model of HDR isolation bearings will be used to predict the seismic responses of a base-isolated multistory building tested by a shaking table. A single set of 10 parameters used in the proposed mathematical model is obtained by combined just two hysteresis loop of eight shaking table test. From the test result, it is concluded that the proposed model of HDR isolation bearing is capable of predicting the seismic response of a base-isolated multistory structure if the model is well calibrated by a set of dynamic tests.

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