高速炉用3次元免震装置における上下方向の剛性のばらつきによるロッキング振動に関する予備研究

抄録

Sodium-cooled Fast Reactor “SFR”, next-generation reactor, is studied and developed. SFR is operated at high-temperature and low-pressure compared with light water reactor. Accordingly, the internal components are thin-wall structure. Securing earthquake resistance is important for seismic design of SFR. Recently, seismic conditions in Japan have become more severe. Because seismic vertical conditions have become more severe, it is necessary to decrease the vertical seismic loading at the structures. The adoption of three-dimensional seismic isolation system is effective to decrease the seismic loading on the structures. When the vertical frequency with the three-dimensional isolation system is low, the rocking vibration occurs. In the case of approximately 3 Hz in vertical frequency, the response in vertical direction is reduced and rocking vibration is reduced. However, rocking vibration occur due to characteristics dispersion of seismic isolation system. In this paper, we confirmed trend on rocking vibration due to dispersion of vertical characteristics of the three-dimensional seismic isolation system by simple analysis model.