Seismic isolation design for JSFR

Okamura, Shigeki*; Eto, Masao*; Kamishima, Yoshio*; Negishi, Kazuo; Sakamoto, Yoshihiko ; Kitamura, Seiji ; Kotake, Shoji*

This paper describes the seismic design of JSFR, which includes the seismic condition, the seismic isolation system and the seismic evaluation of primary component. JSFR employs a seismic isolation system to mitigate the earthquake force. The design seismic loading is made more severe than ever since Niigata-ken Chuetsu-oki Earthquake in 2007. The earthquake force loaded on the primary components has to be mitigated more than that of the previous seismic isolation system. We examined the advanced seismic isolation system by optimizing the performance of the previous seismic isolation system considering the natural frequency of the primary components. The advanced seismic isolation system for SFR was adopted laminated rubber bearings which are thicker than that of the previous, as well as oil dampers. The seismic evaluation of nuclear reactor components under applying the advanced seismic isolation system was performed; the performance of the system was confirmed.