Fatigue strength of fillet welded structural steels: finite elements, strain gauges and reality

Abstract

This work analyses the influence of geometry, residual welding stresses and secondary bending effects on the fatigue strength of fillet welded joints made of structural steels. Joints with main plate thicknesses ranging from 10 to 100 mm subjected both to axial and to bending load with load ratios between −1 and 0.1 were considered. The experimental results were taken from the literature and then re-analysed in terms of local stress field intensity instead of nominal stress. This approach led to the definition of a new unified scatter band valid for structural steels, similar to that defined in the past for welded joints but with new characteristic parameters. The application of the scatter band to local strain fields evaluated by numerical analyses or measured by strain gauges is also discussed.