Fatigue strength of a common steel welded detail through Eurocode 3 and local strain energy values

This paper investigates the influence of the main geometrical parameters of a welded detail, common for structures having various applications, providing a comparison between the recommendations given by the Eurocode 3 and the results achievable through the application of a local approach, such as the Strain Energy Density method. The effect of a complete weldment versus a weldment presenting lack of penetration is investigated as well. Indeed, a full penetration weldment, involving higher costs, is not always needed to ensure failure from the weld toe, a condition to be preferred for monitoring purposes. The fatigue strength estimated for the joint though the local approach showed that the Eurocode 3 significantly overestimates the influence of some geometrical parameter describing the joint, neglecting other important parameters. The results of this study highlight the limitations of a global approach in accounting for different geometrical parameters and show instead the power of a local approach in determining the parameters that may severally influence the fatigue strength. Thus, it allows fatigue assessment through ad hoc experimental campaigns, reducing in this way the costs of such kind of investigations.