Advancing Structural Reinforcement in 3D-Printed Concrete: Current Methods, Challenges, and Innovations

With rapid global urbanization and economic development, 3D concrete printing (3DCP) technology has emerged as an innovative construction method, garnering increasing attention and application. Compared to traditional construction techniques, 3DCP not only reduces resource waste and carbon emissions during the building process but also significantly enhances construction efficiency, demonstrating considerable potential in the construction industry. As 3DCP advances from theoretical studies to real-world applications, providing stable and reliable structural reinforcement solutions becomes essential. This paper focuses on examining various methods to improve the performance of 3D-printed concrete (3DPC) structures. The analysis shows that reinforcement using steel bars, in combination with other materials (mainly fibers and nanomaterials), remains a key strategy for structural enhancement. By integrating diverse reinforcement methods, this study proposes an innovative bidirectional steel mesh layout scheme. Additionally, given the unique nature of 3DPC construction, a critical review of various methods for improving interface bonding strength is included. These findings aim to guide the engineering community in selecting suitable reinforcement solutions for 3DPC.