Research on Seismic Margin Analysis of Operation Nuclear Power Plant

The aiming of seismic margin analysis (SMA) is to evaluate the seismic resistance ability when the targeted earthquake is beyond the design basis. After Fukushima nuclear accident, extra weight has been given to the work of implementing safety inspection and evaluation which attempts to evaluate the safety margins of NPPs under beyond design basis conditions as well as to bring forward some improving measures. Through wide study of methods used in SMA abroad, a conclusion can be made that the EPRI SMA method is maturely ideal for the NPPs under operation and reasonably proper to Qinshan Phase Ⅱ. The analysis results show that the ruggedness of Qinshan Phase Ⅱ can be guaranteed while the seismic margin is 1.5SSE.