Feasibility study on the seismic isolation of pool-type LMFBR

The seismic base isolation systems are very efficient in protecting important internal equipments as well as buildings from earthquake vibration. Many advantages can be anticipated when this system is applied to the most important (in seismic rating) structures such as the FBR plant. The base isolation system composed of laminated rubber bearings and a certain kind of energy dissipators are considered to be the most practical at present. The lead and elastomeric bearing, which has been developed in New Zealand, is a laminated rubber bearing with a lead plug down its center. It provides the combined features of horizontal flexibility and energy absorption capability in a single unit. In order to investigate the feasibility of adopting the lead and elastomeric bearings to the seismic isolation systems of the pool type LMFBR plants, loading tests and shaking table tests were conducted. This paper describes the experimental results of the mechanical behavior and vibration characteristics.