Effect of printing parameters on inter-filament voids, bonding, and geometrical deviation in concrete 3D printed structures

This study presents the effect of different printing parameters including printing speed, extrusion rate, and inter-filament overlapping distance on inter-filament bonding, inter-filament voids, and geometrical deviation in concrete 3D printed structures using Response Surface Methodology. Moreover, this study adopts a central composite design to generate a set of experimental runs and develop a second-order polynomial equation to quantify the effect of printing parameters. Results show that high inter-filament bonding with minimal inter-filament void and geometrical deviation can be achieved at high printing speed and low extrusion rate with 1/8Nd (2.5 mm) inter-filament overlapping distance.