Mechanical and structural performance of reinforcement strategies in 3D concrete printing: A review

Abstract 3D concrete printing (3DCP) has emerged in recent decades as a promising construction technology that minimizes labor‐intensive and time‐consuming processes. Reinforcement integration is essential to ensure structural integrity and durability, particularly for large‐scale applications. While many reviews have focused on reinforcement classifications, there remains a lack of in‐depth evaluation of mechanical and structural performance, automation feasibility, and large‐scale validation. This review addresses these gaps by critically examining three categories of reinforcement: intralayer (fibers, cables, continuous yarns), interlayer (steel rebar, barbed wire, screws), and across‐layer (steel cages, meshes, post‐tensioning). Intralayer reinforcement offers excellent automation compatibility and design freedom, but contributes little to large‐scale load resistance due to discontinuity and low stiffness. Interlayer reinforcement improves bonding and ductility but introduces matrix disturbance and anchorage challenges. Across‐layer reinforcement provides the most reliable structural performance, essential for seismic and load‐bearing capacity, but limited automation maturity and design freedom. Hybrid systems emerge as promising strategies, combining material‐ and structural‐level reinforcement to enhance ductility, toughness, and load capacity, though their integration remains costly, complex, and less automation‐friendly. Current investigations are disproportionately skewed toward flexural behavior, while critical tests such as pull‐out, interlayer bond strength, compression, shear, and seismic loading are underexplored. Future work should prioritize large‐scale/field‐scale and long‐term structural validation, develop standardized fabrication and testing protocols, and advance reinforcement strategies that reconcile automation potential with structural reliability.