Curing with Shrinkage-Reducing Admixtures Beyond drying shrinkage reduction

Shrinkage of concrete, along with the cracking that often accompanies it, has been a continual concern of the concrete construction community.1,2 In the past 20 years or so, numerous shrinkage-reducing admixtures (SRAs) have been developed with the goal of reducing drying shrinkage and delaying or preventing cracking.2-6 Most SRAs function by reducing the surface tension of the pore solution in the concrete. In addition to reducing or slowing drying shrinkage, this reduction in surface tension can also potentially reduce autogenous shrinkage in mortars and concretes with low water-binder ratios as well as reduce evaporative water loss during earlyage curing.6,7 In this article, a consistent theoretical basis for these reductions is presented along with example results illustrating the use of SRAs as potential curing compounds.