Fatigue strength of transverse butt welded joints under random loading. Application of Miner's rule in σmax = σy tests

Abstract

Summary The fatigue strength of transverse butt welded joints is obtained in tests involving the maximum stress σmax being kept the same as the yield strength of the material σy while the minimum stress σmin is randomly varied. The tests involve modification of the stress conditions of actual welded structures containing high tensile residual stress up to the yield strength. The beach marks found on the fracture surfaces of the specimens suggest that, when no distinct beach mark is observed, the crack initiation life occupies a large proportion of the total life. The results obtained show a good fit with Miner's rule, unless mediated by a coaxing effect.