Analysis of stress concentration factor of welded tubular K-joints subjected to axial loads

The geometrical and numerical modelling of welded tubular K-joints is presented in this study.The stress concentration factors along the weld toe in the hot spot stress region for tubular K-joints subjected to balanced axial loads are obtained through experimental tests on two large-scale tubular K-joints.The accuracy of the numerical stress concentration factors is verified from experimental results.The effect of the geometrical parameters on the stress concentration factor of tubular K-joints under axial loads is investigated based on the finite element results of 1 008 K-joints models with different geometries.Finally,a set of parametric equations to predict the stress concentration factor of a tubular K-joint subjected to balanced axial loads is proposed,and these parametric equations are deduced from nonlinear regression and curve fitting technique.The accuracy of the parametric equations is also evaluated.