Study on seismic response of isolated nuclear power plant based on probabilistic assessment, 1; Modeling considering nonlinearity of rubber bearings

Fujita, Satoshi*; Minagawa, Keisuke*; Yamaguchi, Akira*; Takata, Takashi*; Kurisaka, Kenichi 

The response to the input more than assumption is requested in the seismic response analysis used for the Probabilistic Safety Assessment. Rubber bearings used as the isolation system cause nonlinearity in the restoring force when the input more than assumption is received. However, the seismic response analysis method for considering nonlinear of the rubber bearing has not been established. Therefore, this study aims at the development of the seismic response analysis method of an isolated nuclear power plant based on the probabilistic safety assessment. In this paper, isolated building model that the nonlinearity of the rubber bearing is considered is made, the seismic response analysis is done, and the influence that it gives respond was verified. As a result, in horizontal direction, it was confirmed that the increasing tendency of the response acceleration was remarkable because of the increase of the earthquake size. In vertical direction, it was confirmed that the increasing tendency of the response displacement was remarkable.