Engineering estimation of elastic-plastic fracture parameter for circumferential surface cracked pipes: part II

This paper provides validations of the reference stress based J and C* estimations, proposed in part I, for inner, circumferential surface cracked pipes under internal pressure and global bending against detailed 3-D elastic-plastic and elastic-creep FE results. For this purpose, actual tensile properties of two typical stainless steels (TP304 and TP316) are used for elastic-plastic FE analyses and two realistic creep laws are used for elastic-creep FE analyses. For a total of twenty cases considered in this paper, agreements between the proposed reference stress based J and C* estimations and the FE results are excellent. More important aspect of the proposed estimations is that they can be used to estimate J and C* not only at the deepest point of the surface crack but also at an arbitrary point along the crack front