A RESEARCH-PROGRAM FOR DYNAMIC FRACTURE EVALUATION OF JAPANESE CARBON-STEEL PIPES

A research program was developed to investigate the dynamic load effec t on fracture behavior of Japanese carbon steel STS410 pipe. The progr am comprises material tests, pipe fracture tests and development of es timation scheme. Material property tests showed that the flow stress w as nearly constant or slightly increased with strain rate. Pipe tests showed that fracture load was nearly predicted by the net-section coll apse criterion for both quasi static and dynamic loading. Significant dynamic effect was not observed for STS410 carbon steel piping. Crack growth was well formulated by using J-integral parameter for low cycle fatigue with large scale yielding. Combining the crack growth behavio r and unstable fracture criterion, an estimation scheme was newly deve loped and validated for constant amplitude cyclic loading conditions. (C) 1997 Elsevier Science S.A.