Abstract
In order to evaluate fracture performance of steel welded structures, the fracture mechanics approach has been adopted. However, it has frequently been pointed out that conventional fracture mechanics parameters are not necessarily applicable to all cases. This inconsistency is due to the difference of stressβstrain behaviour depending on plastic constraints in the vicinity of a crack tip between the fracture toughness testing specimen and the practical structures. Accordingly, the transferability of the fractureβcontrolling parameter and a new appropriate procedure is discussed.
In the welded joint, moreover, the mismatching of metallurgical/mechanical properties inevitably exists. Mismatching in strength also results in considerable change in plastic constraints. It is very important that the combined consideration of both strength mismatching and transferability for critical assessment of the structural integrity with regard to the unstable fracture of steel welded structures.
The present paper summarizes the recent activities on transferability of fracture toughness data to fracture assessment in structural welded joints, with particular reference to mechanical heterogeneity observed in welded joints.