Probabilistic Nonlinear Analysis of Steel Frame Safety Under Extreme Wind Impact

Abstract

This paper describes the methodology and the results of the safety analysis of the Nuclear Power Plant (NPP) structures under impact of the extreme climatic loads. In the case of the NPP structures, the design criteria are stronger. The requirements of the international agency IAEA and NRC standards are based on the probability of mean return period equal to one per 10 4 years. This probabilistic assessment of NPP structures for Probabilistic Safety Analysis (PSA) level 2 of VVER 440/213 in the case of the extreme wind impact is presented. On the base of the meteorological monitoring of the locality the extreme load parameters were defined for the return period 10 4 years using the Monte Carlo simulations. There is showed summary of calculation models and calculation methods for the probability analysis of the structural resistance. The wind load was determined using the fluid analysis in software FLUENT in ANSYS and experimental analysis in wind tunnel. The general purpose of the nonlinear probabilistic analysis of the NPP structure resistance was to define the safety level of the critical structure elements. The numerical simulations on the base of the LHS method were realized in the system ANSYS and FReET.