Optimisation of Hybrid WAAM Tubular T‐joints

At the construction scale, wire arc additive manufacturing (WAAM) is more likely to complement rather than replace conventional techniques, thereby leveraging the flexibility of WAAM while balancing cost and productivity. Structural connections are ideal for WAAM as they often feature intricate geometries and complex loading conditions, offering opportunities for reduced material usage through structural optimisation. This study investigates topology‐optimised square hollow section (SHS) T‐joints under brace compression. Retaining conventionally manufactured chords, the connection region was optimised for WAAM, with manufacturing constraints incorporated to improve printability. The finite element analysis (FEA) of the optimised T‐joints demonstrated a significantly increased load‐carrying capacity compared to the corresponding benchmarks, highlighting substantial improvements in structural efficiency. Selected optimised and conventional benchmark T‐joints were fabricated for experimental verification. This study confirms the feasibility of applying topology optimisation in hybrid WAAM‐conventional construction, addresses printability constraints, and proposes a novel approach to reducing material usage and enhance automation for structural connections.