The practical result of this experiment may be a means of determining the minimum required curing duration, depending upon the performance criterion. Based solely on the DOH data, one would conclude that the minimum duration of curing is 7 d, regardless of w/c value, for these are the only UWVE specimens that hydrated at a rate equivalent to a SWVE specimen. This recommendation would agree with ACI 308 guidelines.
If the criterion changes from observed DOH to microstructure and durability performance, the fixed 7 d curing may be too burdensome for lower w/c pastes, and insufficient for higher w/c pastes. Delaying exposure to an unsaturated environment until the -30 ºC peak first appears would ensure, at the very least, proper microstructural development. Based on these experimental results, the minimum curing at 25 ºC for the 0.30 w/c, 0.40 w/c, and 0.50 w/c ordinary portland cement pastes are approximately 1 d, 3 d, and 14 d of saturated curing, respectively. Remarkably, these recommendations agree with the recommendations of Powers, Copeland, and Mann [21] that were made nearly 45 years ago.