Fracture behaviour of carbon steel straight pipe with through-wall crack under cyclic loading

摘要

Carbon steel straight pipes form part of the primary heat transport system of nuclear power plants. They may be subjected to dynamic-cyclic loads during earthquake event. This dynamic-cyclic loading significantly affects the fracture resistance and the load carrying capacity of cracked components. Further, for the application of leak-before-break concepts, experimental investigations are very essential. Therefore, the aim of the present study is to investigate the effect of cyclic loading on fracture resistance of through-wall cracked straight pipes. The paper presents details of the cyclic fracture test on a straight pipe and the results thereof. The behaviour of the pipe was compared with the fracture behaviour under monotonic loading. The study has shown that the load capacity of the pipe is reduced under cyclic loading and the failure is by cyclic tearing followed by sudden collapse.