Print time vs. elapsed time: A temporal analysis of a continuous printing operation for additive constructed concrete

Abstract In additive construction, ambitious goals to fabricate a concrete building in less than 24 hours are attempted. In the field, this goal relies on a metric of print time to make this conclusion, which excludes rest time and delays. The task to complete a building in 24 hours was put to the test with the first attempt at a fully continuous print of a structurally reinforced additively constructed concrete (ACC) building. A time series analysis was performed on the events during the construction of a 512 ft 2 (16’x32’x9.25’) building to explore the effect of delays on the completion time. This analysis included a study of the variation in comprehensive layer print times, expected trends and forecasting for what is expected in future prints of similar types. Furthermore, the study included a determination and comparison of print time, elapsed time and construction time, as well as a look at the effect of environmental conditions on the delay events. Upon finishing, the analysis concluded that the 3D-printed building was completed in 14-hours of print time, 31.2-hours elapsed time, or a total of 5 days of construction time. This emphasizes that reports on newly 3D-printed constructions need to provide a definition of time that includes all possible duration periods to communicate realistic capabilities of this new technology.