Fatigue Life Assessment of High-Strength Steel S700 Weldment

In this study, an experimental investigation has been carried out to assess the fatigue life of butt-welded connections made of high-strength S700 steel. A total of 15 specimens, consisting of butt-welded steel with S700MC grade, are subjected to high-cycle fatigue testing. The testing is conducted at a constant frequency of 30 Hz and with a stress range ranging from 50 to 85% of the yield stress. The stress ratio (R) for this study is set at 0.1. Using two different approaches, the natural fitting approach, and the slope m fixed approach, the S–N curve is developed at the conclusion of this research. The fatigue strength of the weldment made with S700MC grade steel is found to be approximately 50–64% higher than the values suggested by the Eurocode.