Growth Curve-Based Continuous Toolpath Design for Improving the Performance of Additively Manufactured Concrete (2026-01)¶

In this study, a novel growth curve-based toolpath planning was developed to generate area-filling and continuous toolpath for extrusion-based additive manufacturing of concrete (AMoC). Unlike conventional methods that rely on FDM-based material deposition, the growth curve-based toolpath utilizes a generative system to create a continuous toolpath that optimally fills the given space, considering AMoC process constraints. The process begins with an input curve subjected to a linear growth function and a user-defined growth factor. The effects of growth factors and other design parameters, including tuning step-over and scale factors, on various performance measures — such as printing time, toolpath continuity, computation time, anisotropic mechanical properties, and print quality — were investigated. Based on experimental and numerical trials, it was confirmed that the proposed method enables efficient and variable area filling with minimal nozzle lifts and sharp turns for the AMoC process. Furthermore, it outperforms the extant zigzag, contour-parallel, and continuous TSP-based tool path methods, while demonstrating a practical pathway toward optimized part printing for infrastructure and architectural applications.