Benchmark analysis on probabilistic fracture mechanics analysis codes concerning fatigue crack growth in aged piping of nuclear power plants

Probabilistic fracture mechanics (PFM) is a rational methodology in structural integrity evaluation and risk assessment of aged piping in nuclear power plants. Several PFM analysis codes have been improved or developed in Japan, such as PRAISE-JNES and PASCAL-SP. Although they were developed for different purposes, some basic functions are almost the same. In this paper, in order to confirm the reliability and applicability of two PFM analysis codes, PRAISE-JNES and PASCAL-SP, a benchmark analysis is carried out using the basic functions in these two codes, considering representative piping systems in nuclear power plants and fatigue as the typical aging mechanisms. We discussed the reliability and applicability of these codes based on a previously proposed criterion to judge quantitatively whether the differences between the analysis results from two PFM analysis codes can be acceptable. Through the benchmark analysis, it is concluded that the analysis results of these two codes are in good agreements quantitatively.