Digital design and parametric study of 3D concrete printing on non-planar surfaces

While significant efforts have been devoted to material and printing process optimisation for 3D concrete printing (3DCP) on flat surfaces, printing on non-planar or complex surfaces remains challenging. In this work, a design-to-printing framework that combines digital models and physical printing processes is developed and validated for 3DCP on non-planar and curved surfaces. Parametric studies are conducted to investigate the correlations between printing parameters, surfaces' slopes, and filaments' geometries. This paper demonstrates that while the printing instability is mainly attributed to inaccurate deposition of filaments accumulated throughout the process, controlling nozzle height is the key for successful printing on non-planar surfaces. Moreover, printings on surfaces inclined at less than 20 degrees comply with the strength-based stability criteria. Printing parameters, such as nozzle height, printing speed and extrusion volume can be tuned to create suitable toolpath and associated GCode for stable printing on complex surfaces.