A Critical Review of the Extrusion-based 3D Construction Printing (3DCP) Technology in the Construction Industry

Abstract

3D printing techniques (also known as additive manufacturing) are maturing and gaining global attentions as an alternative means for full-scale fabrication within the construction industry to increase customization, reduce construction time, and improve affordability. Although there has been significant effort invested over the last two decades in the development of scaled-up 3D construction printing (3DCP) techniques, such as Contour Crafting, D-Shape and Concrete Printing, most of them are based on the extrusion-based processing and there are currently few examples of how such advances could be achieved at a building scale. The issues that caused decisive restrictions on actively adopting the extrusion-based 3DCP techniques within the construction industry are related to: insufficient material performance, implementation of reinforcement, insufficient qualities in surface finishes and rheology control of cementitious materials. It is therefore necessary to review characteristics and challenges of current extrusion-based 3DCP techniques and explore the potential of other 3D printing technologies for better utilization of the technology in the construction industry in the future. The main purpose of this research is to increase our understanding of explicit limitations of 3DCP techniques based on extrusion process and open up the future opportunities for a more efficient and stable 3DCP system.