Stub Column Tests on Concrete‐Filled Wire Arc Additively Manufactured Steel Tubes

Abstract Wire arc additive manufacturing (WAAM) is a robotic metal 3D printing technique that enables the efficient and cost‐effective production of large‐scale structural components with complex geometries. The undulating surface geometry inherent to the WAAM process can be leveraged to enhance the bond strength at the interface between the steel and the concrete in concrete‐filled steel tubes (CFSTs), thereby enhancing the composite action and improving their structural performance. The present paper describes an experimental investigation on the axial compressive behaviour of WAAM CFST stub columns. A total of six WAAM CFST stub columns were tested, encompassing a wide range of diameter‐to‐thickness ratios. Prior to testing, the undulating as‐built geometry of the WAAM steel tubes were captured using 3D laser scanning. The structural behaviour of the stub columns is analysed herein in terms of the axial load‐end shortening curves. The confinement effects enabled by the steel tube are investigated utilising the surface strain fields that were determined by employing digital image correlation.