Research on the attribution evaluating methods of dynamic effects of various parameter uncertainties on the in-structure floor response spectra of nuclear power plant

摘要

Consideration of the dynamic effects of the site and structural parameter uncertainty is required by the standards for nuclear power plants(NPPs) in most countries.The anti-seismic standards provide two basic methods to analyze parameter uncertainty.Directly manually dealing with the calculated floor response spectra(FRS) values of deterministic approaches is the first method.The second method is to perform probability statistical analysis of the FRS results on the basis of the Monte Carlo method.The two methods can only reflect the overall effects of the uncertain parameters, and the results cannot be screened for a certain parameter's influence and contribution.In this study, based on the dynamic analyses of the floor response spectra of NPPs, a comprehensive index of the assessed impact for various uncertain parameters is presented and recommended, including the correlation coefficient, the regression slope coefficient and Tornado swing.To compensate for the lack of guidance in the NPP seismic standards, the proposed method can effectively be used to evaluate the contributions of various parameters from the aspects of sensitivity, acuity and statistical swing correlations.Finally, examples are provided to verify the set of indicators from systematic and intuitive perspectives, such as the uncertainty of the impact of the structure parameters and the contribution to the FRS of NPPs.The index is sensitive to different types of parameters, which provides a new technique for evaluating the anti-seismic parameters required for NPPs.