Seismic isolation of industrial facilities using lead-rubber bearing.

Abstract

This paper presents results obtained from experimental and analytical studies to evaluate isolation performances of a lead rubber bearing as a hysteretic damper. In the experiment, vibration tests were first carried out using a 0.3 scale model (5840 kg mass and 2.2 m x 2.2 m x 1.8 m size) for a base-isolated building which was supported by 2 lead rubber bearings and 2 rubber bearings, in order to investigate the isolation performances of the lead rubber bearings in actual seismic wave excitations. Second, static loading tests were implemented in order to examine restoring force characteristics for the lead rubber bearing. In the analysis, seismic response analyses for the scale model, regarding the vibration tests using the actual seismic waves, were carried out to evaluate the response analytical method for the base-isolated system using the lead rubber bearings. From these results, the following is claritied. ( 1 ) Analytical results for the isolated-building model agree well with experimental results. ( 2 ) The lead rubber bearing reduces the responses sufticiently for the isolated building, and controls the responses well for installed equipment in a practical frequency range.