Optimisation and testing of wire arc additively manufactured steel stub columns

Wire arc additive manufacturing (WAAM), a method of directed energy deposition (DED) for metal 3D printing, is capable producing intricate parts at relatively high rate and low cost. Despite the great potential WAAM applications in construction, knowledge performance structural elements still lacking, geometric freedom yet to be fully harnessed. This study therefore aimed investigating local buckling behaviour carbon steel exploring opportunity improved efficiency through optimisation. An optimisation was initially conducted derive optimal stiffener layouts square hollow sections (SHS) under compression. A total six plain SHS with broad range width-to-thickness ratios, along two strengthened optimised stiffeners, were manufactured via tested. The benchmark profiles examined allow direct comparisons conventionally-produced SHS. laser-scanning carried out capture features specimens, digital image correlation (DIC) adopted full-field measurement their responses during testing. stub columns shown have comparable load-carrying capacities stocky range, but exhibited inferior slender range. Comparisons Eurocode 3 (EC3) resistance predictions showed that existing Class slenderness limit effective width specified EC3 plated structures may overly optimistic owing typically larger imperfections. Finally, stiffeners exhibit significantly over both conventionally-manufactured SHS, bringing disproportionate increases deformation capacity relative mass.