Stress and strain concentrations of completely overlapped tubular joints under lap brace OPB load

Abstract

The stress and strain concentrations of a completely overlapped tubular joint specimen are experimentally investigated under lap brace out-of-plane bending (OPB) load. The experimental results showed that the strain distribution near the weld toe is fairly linear. The maximum strain concentration factor of the joint occurs at the through brace saddle near the lap brace. For the finite element (FE) analysis, both 8-node thick shell and 20-node solid elements are suitable for modelling the joint specimen. A set of parametric equations is proposed for predicting the stress concentration factor (SCF) of completely overlapped tubular joints based on 5184 FE models. The parametric equations are verified against the acceptance criteria of Fatigue Guidance Review Panel. The assessment of the proposed equations is based on the database of FE analysis and test results. The comparison of SCF showed that the existing T/Y-joint parametric equations for predicting the SCF of completely overlapped tubular joints are inappropriate under OPB load.