Multiaxial fatigue analysis of circumferentially butt‐welded steel connection using fiber optic‐based distributed strain sensing

This paper presents a study on the performance of circumferentially butt‐welded steel connections under constant tensile‐tensile axial fatigue and cyclic tensile‐tensile bending tests. The study utilizes fibre‐optic based distributed strain sensing to measure the strains and stresses in the regions of the weld. The results confirm the desired pure bending of the specimen during the fatigue cycles. The suitability of fibre‐optic monitoring for fatigue testing of welds is demonstrated. In addition, the study compares the numerically predicted stresses in the welded connection using Finite Element Analysis (FEA) with experimental results, thereby substantiating the accuracy of the FEA predictions.