A structural strain parameter for a unified treatment of fatigue behaviors of welded components

This paper further investigates into the effectiveness of the structural strain method recently proposed by Dong et al. (2014) to model low-cycle fatigue behavior of welded structures. More precisely, an equivalent structural strain range parameter is introduced and implemented here in order to evaluate fatigue behaviors of welded components spanning both low-cycle and high-cycle fatigue regimes. A large number of well-documented fatigue data of weldments with various joint types, loading modes and base materials have been investigated in detail by using the structural strain approach. These components include gusset-to-plate, plate-to-plate and pipe-to-pipe joint. The fatigue loading varys from load-controlled to displacement-controlled conditions, and the base metals ranges from structural steel of different grades and aluminum alloys as well as titanium alloys. The obtained results show that the equivalent structural strain range parameter enables a unified presentation of the fatigue behaviors of all the test data investigated in this paper.