As to this report, the thermal property value of the laminated rubber used for the seismic isolation system was clarified by the thermal property test for the construction of the method of the analysis of heating interaction behavior that allowed the decline in the damping performance to be evaluated more elaboratively through the adequate reproduction of the heat loss phenomena, and the analysis of heating interaction behavior which simulated the contact condition at the lead plug boundary evaluated by the contact analysis was also implemented. Findings from the results of the said test and analysis were as follows.
1) The thermal property test was implemented by means of the laminated rubber used for the seismic isolation system to obtain the thermal property value for the analysis of heating interaction behavior. However, the obtained thermal property value showed about 20 to 40 percent of the difference from the property value used for the previous report and nevertheless the analysis of heating interaction behavior was implemented to confirm the thermal change in the static loading and after the loading, the adequate reproduction of the test result was failed. This showed it was difficult to model the heat loss phenomena only by the measurement of the thermal property value. The cumulative absorbed energy of LRB was however almost the same regardless of the thermal property value, and it was obvious that the thermal property value did not have the impact on the mechanical characteristics so much.
2) The result of the contact analysis of the lead plug showed that the contact area ratio of the lead plug changed depending on the shear strain. The contact area ratio was about 0.8 even if the shear strain was zero percent and not in complete contact, and almost fixed to 50 percent. In case where the shear strain exceeded 50 percent, the contact area ratio showed decrease as the shear strain increased, and it was confirmed that the ratio was about 0.6 when the shear strain was 100 percent. The strain dependency of the contact area ratio in unloading was confirmed it showed the same tendency in loading. These were found in the limited range of the shape of device, the surface pressure.
3) The method to reduce the thermal conductivity in response to the shear strain was proposed to bring the contact condition of the lead plug and the laminated rubber obtained by the contact analysis to the analysis of heat iteration behavior. In addition, the program for the analysis of heat iteration behavior that used the non-linear thermal conductivity analysis was developed to implement the reproduction analysis to which this model was applied. The result of the analysis accurately reproduced the internal temperature distribution of the equipment without dependence on the loading velocity, and the heat loss characteristics after the loading almost conformed with the test result.
