Seismic Probabilistic Risk Assessment of Nuclear Power Plants

Seismic Probabilistic Risk Assessment of Nuclear Power Plants

Seismic Probabilistic Risk Assessment(SPRA) determines the annual frequency of unacceptable seismic performances of a nuclear power plant(NPP), such as core melt and release of radiation, and has been recognized as an important tool for assessing the seismic risk of NPPs. In this study, the procedures of conventional SPRA methodologies are explored and the seismic risk of a sample NPP for one of the accident sequences is computed using conventional SPRA methodologies. SPRA methodologies typically involve the use of component fragility curves defined as a function of ground-motion parameters, such as peak ground acceleration and spectral acceleration. In future studies, the conventional SPRA procedure will be compared with the new SPRA procedure proposed by Huang et al.(2011), where the component fragility curves are defined as a function of structural-response parameters, such as floor spectral acceelration, and the advantages and disadvantages of those two methodologies are discussed.