On the creep-fatigue structural test of a high temperature discontinuous structure

The objective of this study is to perform creep-fatigue test of Y-shape cylindrical model to validate the NONSTA-VP code that is developed for the detailed inelastic structural analysis and to characterize the creep-fatigue damage development of 316SS structure. In the test model, penetrated defects and surface defects were prepared investigate the damage development ahead of defects. In the fiscal year of 2003, 100 cycles of creep-fatigue loading were applied and the corresponding creep-fatigue damage was rarely observed. Both elastic analysis and inelastic analysis using NONSTA-VP code were performed with collected temperature profile from test and the strain results of analyses agree well with those from the test. The creep-fatigue damage was assessed per ASME-NH utilizing analysis results and the very small amount of damage was obtained of which result coincides with test result. Further cycles of creep-fatigue test is planned to investigate the evolution of creep-fatigue damage and to validate inelastic structural analysis code