NUMERICAL STUDY OF STAINLESS STEEL CIRCULAR HOLLOW SECTION TUBULAR T-JOINTS

This paper reports numerical investigations on stainless steel circular hollow section (CHS) tubular T-joints. Both brace and chord members fabricated from circular hollow section were studied by using general purpose finite element program-ANSYS. In the finite element models, both geometric and material nonlinearities were considered. The axial compression force was applied to the brace member, while the bottom of the chord member of the joint was fixed. The ratio of brace to chord diameter varied from 0.2 to 1.0 so that different failure modes of stainless steel CHS tubular T-joints were observed. The quality of welding which affects the behavior of tubular joints was assessed. It was found that the welding bead should be taken into account in the finite element models in order to obtain accurate results. The joint strengths, failure modes as well as load-deformation curves of all stainless steel CHS tubular T-joints were obtained from numerical simulation. The finite element analysis results were compared with those calculated using the design formulae given in the current CIDECT and Chinese Code for carbon steel tubular joints. It is shown from the comparison that the current design rules are generally conservative for cold-formed stainless steel CHS tubular T-joints.