Evaluation of postulated cross sections with ovality and thinning for 90° pipe bends with circumferential throughwall cracks subjected to in-plane closing bending

A comparative study of postulated cross sections for failure analysis of 90°structurally deformed pipe bends with critical circumferential throughwall cracks was performed. Elliptical and semi-oval cross sections were assumed to determine the collapse loads under in-plane closing bending moment. Finite element analysis was conducted based on elastic-perfectly-plastic material considering geometric nonlinearity and twice-elastic-slope method was...