LEAK AREA AND LEAKAGE RATE PREDICTION FOR PROBABILISTIC RISK ASSESSMENT OF CONCRETE CONTAINMENTS UNDER SEVERE CORE CONDITIONS

The fundamental gap in knowledge for estimating release for probabilis tic risk assessment of concrete containments subject to beyond design basis loads is in estimating leak areas and leakage rates. By evaluati ng the available literature and carefully studying the test results, s everal generic rules are postulated for leak areas and leakage rates o f concrete containments. These rules, coupled with theory-based leakag e flow equations and empirically-based crack roughness constants, prov ide a realistic estimate of leak rates through liner tears in concrete containments.