Influence of practical curing methods on evaporation of water from freshly placed concrete in hot climates

The effectiveness of different curing methods on the evaporation of water from freshly placed concrete is presented. The curing methods employed within the current experimental programme comprised plastic sheeting and burlap and were compared to the evaporation of water from an uncovered concrete surface. Samples were exposed to an ambient temperature of 40°C and a relative humidity of approximately 30% for a period of 72 h. The effectiveness of each curing method was quantified in terms of both the cumulative water loss and rate of evaporation from the concrete surface. When compared to the uncovered surface, both curing systems resulted in a reduction in both the total amount of water loss and rate of evaporation, particularly over the initial 6 h after mixing. A local maximum in the rate of evaporation coincided with the maximum in internal temperature occurring within the concrete, the latter being due to setting of the cement binder.