Enhancing the Shear Properties of U-Shaped Steel Wire Mesh Reinforced 3D Printed Composites (2025-12)¶

3D-printed concrete (3DPC) represents a rapidly developing technology with numerous applications in construction. The properties of 3DPC under both static and dynamic loads can be enhanced by incorporating reinforcement. This study presents a novel reinforcement technique utilizing U-shaped steel wire mesh (U-shape SWM). This technique involves integrating both horizontal and vertical reinforcements during the concrete printing process. Additionally, a new fabrication process was developed using a dual-arm robotic system, with each arm equipped with shaping and welding tools, to autonomously create U-shape SWM structures. An experimental investigation was conducted on specimens reinforced with either flat or U-shape SWM reinforcements under flexural loading. Compared to the specimens reinforced with a single layer of 6-mm flat SWM under a shear-span ratio of 2, those incorporating one layer of U-shape SWM combined with two layers of 6-mm flat mesh exhibited a 200% increase in failure load and a 26.09% increase in cracking load, while the ultimate displacement decreased by approximately 6%. Under a reduced shear-span ratio of 0.5, this reinforcement configuration reached a failure load of 43.6 kN, a cracking load of 16.1 kN, and an ultimate displacement of 11.1 mm. Furthermore, an analytical model based on the strut-tie model was developed to predict the load-bearing capacity of the reinforced specimens. The model predictions showed good correspondence with the experimental results.