The experimental study presented in this paper is aimed at evaluating the seismic performance of integrated isolation/ restraint (I/R) systems for heavy HVAC equipment. Earthquake simulator experiments were conducted on a heavy centrifugal chiller supported by four I/R systems. The peak response quantities of the equipment and the peak dynamic forces induced into the I/R systems were considered as the key components for the seismic-performance evaluation of the I/R systems. The test plan included seismic and system-identification tests and incorporated different input motion amplitudes and different configurations of the restraint components of the I/R systems. The test results showed that limiting the displacement of the equipment by the impacts occurring in the restraint components of the I/R systems resulted in amplification of the acceleration response of the equipment and excessive dynamic forces induced into the I/R systems. Throughout the experiments, the I/R systems experienced dynamic forces much higher than their static design capacity. The configuration variables of the restraint component, particularly the gap size, were proven influential on the seismic performance of the I/R systems. Among different configurations of the restraint component considered in this study, the configuration with the smallest gap size resulted in the best overall seismic performance.

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