Estimation of the Fracture Resistance Curve for Gas Pipelines Using the Single Edge Notched Tension (SENT) Specimen

In this study, fracture resistance curve for API 5L X70 line-pipe steel was estimated by using SENT specimen, which is known to have similar constraint condition to the full-scale pipe. The constraints of structure are known to be affected by geometry, initial crack depth, loading condition and material properties. To assess the constraint effect for various geometries, such as SENB, SENT and full-scale pipe structure, the J-Q analysis was performed using the HRR stress field based on J-integral using finite element analysis. Fracture resistance curve obtained from SENT specimen were performed according to BS 8571 standards and J-R curve & CTOD-R curve were presented, respectively.