Derivation of J-resistance curve for through wall cracked pipes from crack mouth opening displacement

In this paper, factors for calculating the J-resistance curve from the measured crack mouth opening displacement (CMOD) record are derived for circumferential through wall cracked straight pipes subjected to pure bending. Rigorous elastic plastic finite element analyses of around 125 circumferential through wall cracked straight pipes subjected to four point bending have been carried out to validate the proposed equations. The factors have also been validated with a few fracture experimental results on straight pipes. For these tests the J–R curve has been evaluated using the conventional as well as using the proposed factors along with the moment-CMOD record.