Ultimate capacity of a mark II primary containment using new probabilistic failure criteria

In the past few years, new failure criteria to determine the ultimate capacity of nuclear primary containments associated with exceeding probability have been developed. In this paper, a study concerning the Laguna Verde Mark II reinforced concrete containment is reported. This study was accomplished using an advanced non-linear constitutive and finite element model. Analyses were performed for beyond-original-design pressure and temperature assumptions. The paper describes the non-linear analysis methodology, the various failure criteria, and the application of the results in a probabilistic framework. The probabilistic approach addresses criteria for predicting liner tear, penetration failure, and through-wall shear failure. It attempts to assign reasonable estimates of leak area to different failure mechanisms and it allows the evaluation of conditional probabilities for the postulated severe accidents selected. (orig.)