Buildability Analysis of 3D Concrete Printing (2026-01)¶

Accurate evaluation of 3D concrete printing (3DCP) buildability is critical for quality assurance and continuous construction. However, existing numerical models for 3D 3DCP struggle to simultaneously capture the full structural-scale behavior and realistic portrayal of the printing process, limiting predictive accuracy. While fluid-like material models, exemplified by computational fluid dynamics (CFD), accurately simulate the printing process, they are computationally prohibitive for large-scale structures. Conversely, solid-like material models utilizing typical element activation strategy in finite element analysis (FEA) efficiently predict structural performance but inadequately represent the printing process. To bridge this gap between simulation efficiency and process fidelity, this study proposes a finite element framework incorporating the Drucker-Prager (D-P) model with a segment-by-segment activation strategy, dynamic nozzle constraint, and extrusion pressure effects to simulate full-scale printing processes with enhanced fidelity. The innovation lies in modeling nozzle-induced constraints on newly extruded material to reduce positional deviations during segment activation and explicitly accounting for extrusion pressure on underlying layers. Compared to experimental and numerical results of three typical 3DCP structures (thin-walled cylinders and straight thin wall) reported in the literature, this model exhibits an 8.4%-26.7% reduction (thin-walled cylinders) in prediction error for experimental failure layers compared to literature methods. Furthermore, it accurately captures asymmetric collapse of Cylinder 1 and elastic buckling due to one end out-of-plane deformation of straight thin wall. This framework provides a robust tool for optimizing 3DCP parameters and advancing engineering applications.