Inelastic energy absorption factor for the seismic capacity evaluation of NPP structures

In order to assure the safety of NPP structures, margin of safety or conservatism in incorporated in each design step. Seismic risk evaluation of NPP structures is performed based on the realistic capacity and response of structure eliminated the safety margin and conservatism. In this study, the comparative study on the various evaluation methods of the inelastic energy absorption capacity was performed. The inelastic energy absorption capacity due to the nonlinear behavior of structures has significant effect on the results of seismic probabilistic risk assessment. And the comparison study of the HCLPF values according to the inelastic energy absorption factors was performed. As a conclusion, it is essential to identify the system ductility and story ductility of structures correctly for the seismic risk assessment