CONSTRUCTION METHOD OF THE NEAR FAULT SEISMIC DESIGN SPECTRUM FOR NUCLEAR POWER PLANTS BASED ON PROBABILISTIC SEISMIC HAZARD ANALYSIS

Nuclear power is efficient and clean energy. The construction of inland nuclear power plants in the future needs to consider the near-fault effect of ground motions. However, the effect on the design spectrum of nuclear power plants in China has not been taken into account. Based on a large number of real ground motions including near-fault pulse-like and non-pulse records, the amplification effect of pulses on the acceleration spectrum is studied, and a modified near-fault pulse amplification coefficient model is established. The effect of near-fault pulse is then introduced into the probabilistic seismic hazard analysis, and the uniform hazard spectra are calculated for a scenario fault model. By decomposing the result of the seismic hazard analysis, the most dangerous earthquake magnitude and fault distance for a site are obtained. They are then used in the attenuation relation to calculate the design spectrum of the site. Finally, the design spectrum is modified by the near-fault pulse amplification coefficient, and the seismic design spectrum considering the near-fault pulse effect is obtained. The calculation method of the seismic design spectrum for nuclear power plant sites is provided in the framework of probabilistic seismic hazard analysis. The effect of near fault pulse-like ground motion is considered in this method.