Development of seismic isolation technology for nuclear power plant. Seismic fragility evaluation of equipment

In order to respond the regulatory requirement of residual risk evaluation, a research on residual risk evaluation of the seismic isolated plants is proceeding as a part of the Japan national project of seismic isolation. Seismic response characteristics of the seismic isolated buildings show strong non-linearity and large displacement because of the vibration characteristic of the seismic isolation system. Therefore, response characteristics specific to the seismic isolated buildings such as non-linear response and relative displacement between isolated building and non-isolated building shall be considered in the fragility evaluation methodology for equipment of the seismic isolated plants. This paper focuses on the seismic fragility evaluation of equipment of the seismic isolated plants considering the relative displacement and non-linear response of the buildings. (author)