Application of weight function technique for stress intensity factor and failure assessment diagram with a realistic stress profile

An engineering approach to calculate the stress intensity factors of a semi-elliptical crack is presented. A 2-dimensional solution is derived through weight function, by reflecting on the physical character of cracks. Flaw assessments were performed by the application of DPFAD approach with the K-1 calculation for the realistic stress profile through weight function technique. The assessment points in DPFAD curve resulted in the increased safety margins. These results show the sufficient conservatism in the application of DPFAD with the weight function technique for flaw assessments, when ductile failure is expected.