Tests of cold‐formed austenitic stainless steel circular tubular T‐joints

Abstract Experimental investigation of cold‐formed austenitic stainless steel (CFASS) tubular T‐joints are presented in this paper. The CFASS tubular joints were fabricated by braces and chords with circular hollow sections (CHS). The CFASS tubes had five different cross sections (d×t in millimetre) of 60×2.8, 76×3.0, 114×3.0, 140×3.0 and 165×3.0, where d and t are the nominal outer diameter and thickness, respectively. Each of these sections was used as the chord member of the T‐joints. The corresponding brace member was paired by selecting the five nominal section sizes that had outer diameter smaller than or equal to that of the chord member. Hence, the geometric parameters of the CHS T‐joint specimens were varied, including the ratios of brace diameter‐to‐chord diameter ( β ), chord diameter‐to‐chord thickness (2 γ ), and brace thickness‐to‐chord thickness (τ). A total of sixteen CFASS CHS T‐joints were tested by applying axial compression through the brace without preloading in the chord. The structural behaviour of the CFASS CHS T‐joints in terms of load‐deformation curve, strength and failure mode were obtained. The test strengths were compared with the predictions by using design equations for carbon steel CHS T‐joints provided in CIDECT and EN‐1993‐1‐8. It is shown that these predictions are generally unconservative.