Fatigue Strength of Transvers Butt Welded Joints under Random Loading

Application of Miner's Rule on σ_max=σ_y Test Results

Abstract

The fatigue strength of transverse butt welded joints has been obtained by the tests in which the maximum stress, σ_max, was kept to be the yield strength of material, σ_y, while the minimum stress, σ_min, was changed randomly. These tests modified the stress condition of real welded structures which contains the high tensile residual stress up to the yield strength in magnitude. It was revealed from the beach marks on the fractured surfaces that the fatigue crack initiation life shared the large portion of total life. Miner's rule could be applicable except for a case in which the fatigue life was prolonged with the coaxing effect.