It's probably not going to win any design awards, but the U.S. Marines have scored a first. The New York Post reports:
Marines have used a specialized 3D concrete printer to print a 500-square-foot barracks room in just 40 hours.
The innovative project created the world’s first continuous 3D-printed concrete barracks, according to the Marine Corps.
Harnessing the world’s largest concrete printer, the Additive Manufacturing Team at Marine Corps Systems Command teamed up with Marines from I Marine Expeditionary Force.