Extrusion‐based 3D concrete printing (3DCP) offers automated and material efficient construction, but remains constrained by planar slicing methods that assume flat printing beds—a limitation incompatible with irregular construction‐scale terrains. This study develops and validates a conformal slicing algorithm for printing on sloped surfaces, enabling transformation of inclined terrains into flat, level surface as a first step toward printing slab‐on‐grade foundations. Through systematic experiments, the effect of nozzle speed, extrusion rate, nozzle height, slope angle, and toolpath direction on filament geometry and stability were quantified. The data analysis focuses on filaments printed parallel to the slope, which exhibited the most stable toolpath direction. The characteristics of these filaments were classified into four quality categories, establishing experimentally validated parameter ranges for stable deposition on slopes up to 35°. Experimental results were analyzed using a data‐driven regression‐based prediction model that demonstrated high accuracy on flat surfaces (90%–98%) and consistently acceptable performance on sloped surfaces (80%–96%). The developed algorithm employs variable layer heights, recursive slope recalculation, and constraint‐based parameter validation to maintain constant wall thickness while reducing surface inclination layer by layer. A validation experiment on a 30° slope confirms the successful prediction of the minimum number of transition layers required to achieve flat surface within the verified parameter ranges.
Farrokhsiar et al. (Tue,) studied this question.