Nonlinear Probabilistic Analysis of the Reinforced Concrete Structure Failure of a Nuclear Power Plant Considering Degradation Effects

This paper describes the reliability analysis of a concrete containment for VVER 440 under a high internal overpressure considering nonlinear behavior of reinforced concrete structure. The probabilistic safety assessment (PSA) aims at an assessment of the probability of the concrete structure failure under the excessive overpressure. The non-linear analysis of the concrete structures was taken. The uncertainties of the loads level (long-time temperature and dead loads), the material model (concrete cracking and crushing, behavior of the reinforcement and liner), degradation effects and other influences following from the inaccuracy of the calculated model and numerical methods were taken into account in the response surface method (RSM). The results of the reliability analysis of the NPP structures are presented.