3D CONCRETE PRINTING: MACHINE AND MIX DESIGN

3D concrete printing is an innovative construction method that promises to be highly advantageous in the construction field in terms of optimizing construction time, cost, design flexibility, error reduction, and environmental aspects. Concrete is extruded through a nozzle to build structural components layer-by-layer without the use of formwork or any subsequent vibration. The contribution of this study is to identify and resolve the various design and operational constraints of 3D concrete printing, which are of vital importance for future development of this construction technique. This paper broaches the topic in two different phases: designing the printing machine on one hand, and designing the concrete mix to be used on the other. Experimental results are presented concerning the mix design and the tests performed to determine the fresh and hardened concrete properties. Due to the scarcity of published studies on concrete properties used in 3D printing, the results might be invaluable to the future of this technology. The study may lend itself to become the blueprint for future bigger-scale projects such as creating whole buildings using 3D concrete printers.