Application of the simulation based reliability analysis on the LBB methodology

Abstract

Guidelines on how to demonstrate the existence of Leak Before Break (LBB) have been developed in many western countries. These guidelines, partly based on NUREG/CR-6765, define the steps that should be fulfilled to get a conservative assessment of LBB acceptability. As a complement and also to help identify the key parameters that influence the resulting leakage and failure probabilities, the application of Simulation Based Reliability Analysis is under development. The used methodology will be demonstrated on the assessment of through wall leakage crack stability according R6 method. R6 is a known engineering assessment procedure for the evaluation of the integrity of the flawed structure. Influence of thermal ageing and seismic event has been elaborate.