Effect of ultimate behavior on seismic response of structure and equipment

Abstract

In recently year, large earthquakes have been observed in Japan, and installation of seismic isolation system can be considered in many fields, such as nuclear power plant (NPPs) and modern architecture, in terms of greatly reduction of seismic force. To introduce seismic isolation system into NPPs, the significant improvement of the safety and reliability can be expected. For the purposes of this paper, a slip and hardening of isolation rubber bearing and nonlinear behavior of building structures are considered as the ultimate characteristics that would affect to seismic risk of isolation device and/or superstructure. Furthermore, the effect of the ultimate characteristics on seismic risk of NPP and equipment and piping system in a building is investigated. As a result, although ultimate characteristics of building structure does not affect to the seismic risk of isolation system, the characteristics significantly affect to the seismic risk of equipment and piping system in NPP buildings.