Effectiveness of Different Solutions to Reduce Plastic Shrinkage in Hot Climate Concreting

Hot climate concreting requires that some practices are used to reduce the undesirable effects caused by excessive water evaporation from the concrete surface, which tends to induce plastic shrinkage cracking and thereby reduce durability. This research highlights the effectiveness of different solutions to reduce plastic shrinkage: curing agent, cold water and cover with plastic sheet. Two levels fractional factorial array experimental design was used to reduce the number of tests, and allowed studying both the effect of different factors and interaction between factors. The measured parameters include: plastic shrinkage crack in 10 x 10 x 40 cm specimens, and compressive strength and rate of evaporation. A climatic chamber was used to simulate the hot climate. The results indicate that to minimize the plastic shrinkage the most adequate solution is the application of curing compound followed by the use of a plastic sheet cover. The most effective solution to decrease the evaporation is a plastic film sheet cover