Fracture mechanics safety analysis of components based on fracture mechanics characteristics combined with multiaxiality of the stress state

Currently several parameters for quantifying the crack tip constraint in fracture mechanics specimens as well as in cracked components are under discussion. The parameters are briefly described and compared on the basis of analyses of fracture mechanics specimens. The parameters are able to show loss of constraint, but for high constraint situations the predictions are inconsistent. It is shown that one parameter is able to explain different fracture modes at the same load level for a small scale fracture mechanics specimen and a large scale component like specimen.