CRACK RESISTANCE OF AUSTENITIC PIPES WITH CIRCUMFERENTIAL THROUGH-WALL CRACKS

For a monotonously increasing load the correct evaluation of the crack resistance properties of a structure is essential for safety analyses . Considerable attention has been given to the through-wall case, this is generally believed to be the controlling case with regard to compl ete pipe failure. The maximum load conditions for circumferential crac k growth in pipes under displacement-controlled loading has been deter mined. The need for crack resistance curves, measured on circumferenti ally through-wall cracked straight pipes of austenitic stainless steel 316 L under bending, is emphasized by the limitation in the data rang e from small specimens and by the differences in the fracture mechanic s procedures. To address these issues and to improve calculational met hods a joint fracture mechanics programme is being performed by Electr icite de France, Novatome and Siemens-Interatom. The working programme contains experimental and theoretical investigations on the applicabi lity of small-specimen data to real structures.