Weibull stress analysis for an embedded crack in reactor pressure vessels under pressurized thermal shock

Abstract

This paper describes the Weibull stress approach in predicting the cumulative probability of cleavage fracture for an axially embedded crack in the wall of a reactor pressure vessel (RPV) subjected to a thermal-mechanical transient typical for an accidental, pressurized thermal shock (PTS) event. This study demonstrates the need for detailed elastic-plastic analyses in the integrity assessment of RPVs under PTS loadings, and proposes both a simplified approach and a refined approach to assess the probability of fracture for RPVs subjected to such events.