3D Printed Concrete

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Development of 3D printed concrete (3DPC) began about twenty-five years ago and is now estimated to be at an overall technology readiness level of TRL 6-7. As it approaches operational readiness, 3DPC is poised to revolutionize the construction of buildings and infrastructure. In its current state, 3DPC is already being employed with elevated oversight to build habitable structures with superior strength and resilience.

For 3DCP to reach its full potential, production and quality control processes have to be developed that allow field-based production over a wide range of ambient environmental conditions, material properties, equipment configurations, and construction applications. ARtx is focused on developing these processes.

While this market is small due to technology readiness, habitable structures are currently being built for commercial and military applications.

Commercial Applications

3DCP is an emerging market with significant near-term growth projections. 3DCP is poised to revolutionize the construction of buildings and infrastructure with primary drivers being addressing the shortage of labor, reducing construction waste, increasing productivity, and lowering the carbon footprint of construction.  

Military Applications

The nature of combat, and the Warfighters’ role in it, is evolving due to changes in our adversaries. In response, the military is developing agile and contingent basing approaches that shift operations from centralized infrastructure to a network of smaller, dispersed, and often austere locations. Concrete printing offers an outstanding opportunity to develop and sustain expedient basing needs as it provides significant improvements over traditional construction related to logistics, materials, labor, cost, training, and time to construct/repair facilities and infrastructure. 

ARtx is currently performing concrete printing research in association with the National Institute of Standards and Technology (NIST), part of the U.S. Department of Commerce.

Project Title: Sentinel 4.0tm: Measurement and Control System for 3DCP Interlayer Bond Strength

Technical Abstract: The construction industry is poised for a major transformation through the additive manufacturing approach of field-based concrete printing, an emerging technology using large-scale 3D printers to construct physical infrastructure. Most 3D printing is performed in a controlled environment. In field-based construction, many factors, especially environmental ones, affecting printed concrete product quality are difficult to control. These factors drive the need for field-based quality control methods. A significant hurdle to the anticipated growth of field-based concrete printing is consistency of strength in the bond between successive layers of the printed cementitious materials. 

The end goal of this work is to develop a commercial system for measuring and controlling the quality of this interlayer bond strength under multiple environmental conditions likely to be encountered in the construction industry, including water content, temperature, humidity, wind, and dust. The initial research focuses on identifying characteristics of the mortar after it has been placed in varying environmental conditions. These characteristics will be used to build a commercial system that monitors the mortar in the previous layer and current layer during placement and adjusts the output of the printer in real-time to obtain optimal interlayer bond strength. 

Commercial Applications: This product is answering an industry call to develop automated quality control and monitoring systems, particularly for the interlayer bond, to facilitate large scale adoption of concrete printing. As either original or aftermarket equipment, this system will provide a commercial solution to a real-world problem and advance market acceptance of printed concrete. As a digital device, this system will create a large database of field-based information that can be used to support continuous improvement for equipment, standards, specifications, and processes.