Sulla propagazione della resistenza a fatica di giunzioni saldate sollecitate da carichi multiassiali

The present study addresses the problem of predicting the multiaxial fatigue strength of welded connections when estimations are performed using nominal stresses. In particular, two different approaches are here systematically compared: the modified Wöhler curve method (as recently reformulated by Susmel and Tovo [1]) and the procedure proposed by the Eurocode 3 [2]. The accuracy in estimating the multiaxial fatigue life of the two considered methods was evaluated by using a number of data sets taken from the literature and generated testing different welded details under inphase and out-of-phase biaxial fatigue loading. The modified Wöhler curve method was seen to be successful in predicting the multiaxial fatigue strength of the analysed welded details giving an higher accuracy level compared to that obtained by applying the Eurocode 3 procedure. Finally, the modified Wöhler curve method was employed to predict the fatigue strength of two welded details subjected to in-phase biaxial fatigue loading.