Seismic Fragility Analysis of a CANDU Type NPP Containment Building for Near-fault Ground Motions

In this study, the seismic fragility of a CANDU (CANada Deuterium Uranium) containment building is estimated by performing the nonlinear seismic analysis for the near-fault earthquakes. The lumped mass model of the containment building was used for a nonlinear dynamic time history analysis. The tri-linear skeleton curve was used for the nonlinear behavior of the prestressed concrete containment building. In order to estimate the inelastic nonlinear response of the containment, the maximum point oriented model was used for the hysteretic rule of the shear deformation. For the nonlinear seismic analyses, 30 set of real near-fault earthquake records were used as the input motion. The seismic responses and seismic fragility of the containment for the near-fault ground motions are compared with the responses and fragility for the design ground motion generally used in Korea.