Abstract
Fatigue life prevision of spot welded joints is a very difficult problem particularly when complex structures with different spot welds are present.
The procedure here proposed is based on the formulation of an assembled spot weld element whose structure belongs to the theoretical elastic solution of the region next to the spot weld.
With this element, the actual stiffness of each spot weld is easily accounted, thus avoiding the request of an overwhelming F.E.M.
This modelling technique provides a conventional stress, the Extrapolated Radial Stress (E.R.S.), whose value characterises the tensional field surrounding the spot edge. The progressive damaging can also be accounted leading to an equivalent ERS.
The procedure is applied in the paper on a complex specimen and is partially validated by means of experimental data.