Cold‐formed steel T‐joints with semi‐oval hollow section chord: Experimental insight and finite element modelling

Experimental study and finite element modelling of cold‐formed steel T‐joints with semi‐oval hollow section (SOHS) chord are presented. The rectangular or square hollow section (RHS/SHS) brace was welded to the flat flange of SOHS chord by robotic gas metal arc welding. Twelve SOHS T‐joints with brace‐to‐chord width ratio β from 0.29 to 0.89 were tested with the chord simply supported and the brace axially compressed. The joint strengths, failure modes and load‐deformation responses are discussed. The feasibility of the current design provisions in the CIDECT and Eurocode 3 initially developed for RHS T‐joints was examined. Generally, the predictions by these design methods are quite conservative for T‐joints with cold‐formed steel SOHS chord. In addition, a finite element model was developed to simulate the cold‐formed steel T‐joints with semi‐oval hollow section chord. Details of numerical model, including element type and mesh size as well as heat affected zone and cold‐working effect considerations, are described. The model was verified against the test results in terms of joint strength and load‐deformation response.