In a world first, the US Armed Forces has 3D printed a barracks out of concrete on site at an army base, in less than two days.
The Marine Corps Systems Command (MCSC) constructed the 46-square-metre building in 40 hours at the US Army Engineer Research and Development Center in Champaign, Illinois.
"This is the first-in-the-world on-site continuous concrete print," said Captain Matthew Friedell, a project officer from the MCSC additive manufacturing team. "People have printed buildings and large structures, but they haven't done it on-site and all at once."
The barracks has a slightly undulating facade with visible striations where the printer has added layer upon layer of concrete.
The MCSC teamed up with a task force from the marines to build the barracks, which required four people to supervise and refill the printer with concrete over the course of the 40 hours.
Friedell said the process could be reduced to one day with the help of a robot to do the mixing and pumping. Usually, to construct a barracks manually out of wood would take ten marines five days.
The project was a field test to evaluate the potential of 3D-printed construction. The MCSC additive manufacturing team wants to see the technology more widely used in the Marines.
"In 2016, the commandant said robots should be doing everything that is dull, dangerous and dirty, and a construction site on the battlefield is all of those things," Friedell continued. "In active or simulated combat environments, we don't want marines out there swinging hammers and holding plywood up."
"Having a concrete printer that can make buildings on demand is a huge advantage for Marines operating down range."
Friedell said the technology could also advantage communities when the military was on humanitarian or disaster-relief missions.
Major advances have been made in recent years as architects and engineers have explored the potential of 3D printing in construction.
In the civilian world, Arup and CLS Architetti used a portable robot to 3D-print a concrete house at this year's Milan design week, while the Eindhoven University of Technology will 3D print concrete houses in the Dutch city that will be made available to rent.