Testing and analysis of optimised wire arc additively manufactured steel trusses

Abstract Wire arc additive manufacturing (WAAM) is a method of metal additive manufacturing (AM) that can be used to fabricate optimised large‐scale structural elements of complex form in a cost‐effective manner, opening up opportunities to unleash the true potential of structural optimisation. To demonstrate this potential, two optimised steel cantilever trusses were fabricated by means of WAAM and tested to investigate their structural performance. The tested specimens comprised members of tubular cross‐section of varying diameter and thickness. The geometric features of the tested specimens were determined using 3D laser scanning, while digital image correlation was employed to monitor the displacement and strain fields during testing. Full details of the experimental programme are provided; the obtained results are analysed and comparisons against equivalent conventional reference designs are made. The results of complementary numerical simulations, undertaken to gain further insight into particular features of the structural response of the examined specimens, are also presented. The structural efficiency of all optimised trusses, as measured by the capacity‐to‐mass ratio, was found to be at least 80% higher than that of the corresponding reference designs, underlining the benefits in terms of structural efficiency that can be achieved by the combination of WAAM with advanced optimisation methods.