Multi-scale fabrication and challenges in 3D printing of special -shaped concrete structures

Abstract

3D-printed concrete (3DPC) has demonstrated substantial potential for fabricating geometrically complex structures through its inherent capabilities of parametric design flexibility and formwork-free construction. This review systematically examines the critical triad of structural design, material property control, and deposition technologies essential for 3DPC of non-standard geometries. In structural design, the synergistic integration of biomimetic principles with topology optimization enables lightweight configurations while maintaining material efficiency. For material properties, precisely controlled chemical coagulation and physical flocculation processes effectively mitigate strength deficiency and deformation challenges during rapid concrete deposition. Regarding deposition technologies, the implementation of modular printing strategies, auxiliary support systems, and injection 3D-printed concrete methods demonstrates measurable improvements in both structural integrity and manufacturing efficiency. Although challenges persist in large-scale applications, continuous advancements in automated process control and material innovation suggest transformative potential for architectural engineering applications.