Enhancing 3D Concrete Printing Buildability with Non-Planar Layering (2024-09)¶

This paper explores improvements in 3D Concrete Printing (3DCP) buildability using non-planar layering. Our proof-of-concept experiment validates the assumption that nonplanar layering enhances the buildability of overhangs and vaults. To test this, we designed an object comprising two columns with a Gothic arch and overhangs on the upper part, resulting in a continuous wall at the top. The object measures approximately 1.5 meters in length, 400 mm in width, and 700 mm in height. The design was executed to maintain the centre of mass in the centres of the columns across all print layers, mitigating unwanted deformation. The overhang angle ranged continuously from 0 to 70 degrees. The object was modelled in Rhinoceros software, and G-code for both planar and non-planar printing was generated in Grasshopper. Both samples were designed to use the same amount of material, print length, and print time. We printed these using a cementitious mixture with plastic fibres and an additional accelerant mixed in the nozzle on a gantry printer. Throughout the printing process, we conducted careful observation and monitoring to detect any instances of buckling or collapse. Post-print measurements were carried out to evaluate the deformation of the printed objects, revealing a reduction in deformation with non-planar printing. This paper discusses the analysis of results and proposes a workflow for future data preparation for non-planar slicing.