Shaking table tests on failure characteristics of base isolation system for a DFBR plant

Abstract

The building of a demonstration fast breeder reactor (DFBR) plant in Japan is planed to be base isolated in the horizontal direction. To verify the seismic safety of the isolation system, a series of shaking table tests was conducted using a reduced scale model with three types of base isolation system, natural rubber bearing with steel damper (NRB+SD), lead rubber bearing (LRB), and high damping rubber bearing (HRB). The results of these tests showed NRB+SD, LRB and HRB were within the stable domain (not hardening) at 1×S2 (maximum acceleration 3.80 m s −2) input, and were nearly hardening at 2×S2 input. None of the rubber bearings broke at 3×S2 input, which was the design limit. All these bearings broke at over 4×S2 input.