Influence of weld geometry on stress concentration factor distributions in tubular joints

Abstract

Fatigue design of welded tubular joints relies on an extensive number of parametric equations that allow calculation of the stress concentration factors at characteristic locations around the weld circumference. These equations were developed with finite element models that either do not include a weld geometry or include a simplified representation thereof. This paper presents a new approach for modeling American Welding Society D1.1 standard compliant welds with different geometries. The generated finite element models are used to study the effect of different weld geometries on the stress concentration factor distributions in tubular joints. The results show that the geometry of the weld has a strong influence on the magnitude of the critical stress concentration factor, the shape of the stress concentration factor distribution and the expected failure location. Finally the authors highlight the need for more comprehensive guidelines regarding the determination of complete stress concentration factor distributions from finite element simulations.