Depending on the structural form and the strength of the vertical seismic force, a seismically isolated structure may experience a rocking motion during earthquake, which leads to the uplifting on one side and could cause the tensile force in the isolator bearing. The rubber isolator bearings are known to be capable of carrying a little tensile force but their tension capacity has not been utilized in practice because of the cavitation phenomenon which occurs when the rubber bearing is subjected to a certain degree of tension. Comprehensive research regarding this phenomenon on the rubber bearing is rarely found and therefore the aim of this dissertation is to provide an overview of the mechanism of cavitation phenomenon as well as the consequence of cavitation on the properties of the rubber bearing. For that purpose, different types of elastomeric bearings are analysed numerically and experimentally. Furthermore an attempt was made to comprehend the change in the global response of the structural system due to the varying vertical stiffness of the elastomeric bearing by means of the time history analysis and the linear response spectrum analysis with the mode superposition. These simulation results indicate that the collapse of the structure may be averted, even if the excessive overturning moment of the structure causes the cavitation damage in the elastomeric bearings, unless bearings are completely torn. Also the benefit from the hardening of the bearing under high compression is noticeable to reduce this overturning moment. This fact leads to the idea that some additional compression springs along the outer edge of the structure could replace the often troublesome tension anchoring construction in order to prevent the excessive rocking motion. These additional compression springs should be activated only when a higher degree of the rocking motion appears and as an example for this spring, the elastomeric bearing, perhaps with a low-friction gliding top surface, would be suitable.    «

Depending on the structural form and the strength of the vertical seismic force, a seismically isolated structure may experience a rocking motion during earthquake, which leads to the uplifting on one side and could cause the tensile force in the isolator bearing. The rubber isolator bearings are known to be capable of carrying a little tensile force but their tension capacity has not been utilized in practice because of the cavitation phenomenon which occurs when the rubber bearing is subjected...    »