Local and Non-Local Approaches to Fatigue of Weldments: State of the Art and Possible Developments

This paper attempts to critically review some numerical methods for fatigue strength assessment of welded joints by means of stress analysis tools (usually FE models). In particular, it focuses on the significance of geometrical model, by distinguishing beams from shells and solids, more than distinguishing among nominal, structural and notch stress type. In addition, basing on continuous mechanics theories, a distinction between “local” and “non-local” stress approaches is proposed. Finally the advantages of notch stress approaches are showed by commenting also problems connected to multiaxiality and three-dimensionality of stress state