N. Soneda et T. Onchi, BENCHMARKING STUDIES OF PROBABILISTIC FRACTURE-MECHANICS ANALYSIS CODE, PROFMAC-II, FOR ASSESSING PRESSURIZED THERMAL-SHOCK EVENTS OF REACTOR PRESSURE-VESSEL INTEGRITY ISSUES, Journal of Nuclear Science and Technology, 33(1), 1996, pp. 87-98
The probabilistic fracture mechanics analysis code, PROFMAC-II, was de
veloped and benchmarked for postulated pressurized thermal shock (PTS)
events of pressurized water reactor pressure vessel integrity issues
by participating the PTS benchmarking activities organized and managed
jointly by U.S. Nuclear Regulatory Commission (USNRC) and Electric Po
wer Research Institute (EPRI). Three different sets of benchmarking pr
oblems were assigned to participants for the studies in sequence. The
initial and second sets were preparatory to the third set. Results fro
m the sequential benchmarking activities were that for axial flaw anal
yses probabilities of crack initiation were identical to those for ves
sel failure and the scatter of probabilities among four participating
codes was small, while for circumferential flaw analyses probabilities
varied widely. It was eventually verified that the same probabilities
were achievable by unifying procedures for simulating material proper
ties. Performance of the PROFMAC-II code was excellent in terms of con
sistency and adequacy among the four codes and the eight organizations
which took part in the studies. Several issues relevant to analysis t
echniques and input variables were pointed out for further improvement
of the codes.