OS0817 Elastic plastic fracture mechanics method for a pipe having multiple circumferential cracks based on reference stress method

Abstract

The elastic plastic fracture mechanics methods defined in the Fitness-for-Service Codes of Japan Society of Mechanical Engineers is applicable limited to the single defect. However, multiple stress corrosion cracks were observed in the same weld joint of recirculation system piping of boiling water reactors. The J integral evaluation methods based a reference stress method was developed for a pipe having multiple circumferential cracks on the same plane, and Z-factor used in the elastic plastic fracture mechanics methods was proposed.