Resumen
In November 2019, U.S. Marines, Air Force, and Army Corps of Engineers personnel demonstrated the viability and simplicity of three-dimensionally (3D)-printed construction in a controlled environment at the U.S. Army Engineer Research and Development Center?Construction Engineering Research Laboratory in Champaign, Illinois. The tri-service exercise spanned three days and culminated in the construction of three 1 m × 1 m × 1 m (3 ft × 3 ft × 3 ft) concrete dragon?s teeth (square pyramid military fortifications used to defend against tanks and armored vehicles) and several custom-designed objects. The structural components were printed using a custom-built, gantry-style printer called ACES Lite 2 and a commercially available, proprietary mortar mix. This paper examines the viability of using 3D-printed construction in remote, isolated, and expeditionary environments by considering the benefits and challenges associated with the printing materials, structural design, process efficiency, labor demands, logistical considerations, environmental impact, and project cost. Based on the results of this exercise, 3D-printed construction was found to be faster, safer, less labor-intensive, and more structurally efficient than conventional construction methods: the dragon?s teeth were printed in an average of 57 min each and required only two laborers. However, the use of commercially procured, pre-mixed materials introduced additional cost, logistical burden, and adverse environmental impact as compared to traditional, on-site concrete mixing and production. Finally, this paper suggests future applications and areas of further research for 3D-printed construction.