What is concrete curing?

Curing is the process of controlling the rate and extent of moisture loss from concrete during

cement hydration. It may be either after it has been placed in position (or during the manufacture of concrete products), thereby providing time for the hydration of the cement to occur. Since the hydration of cement does take time – days, and even weeks rather than hours – curing must be undertaken for a reasonable period of time if the concrete is to achieve its potential strength and durability. Curing may also encompass the control of temperature since this affects the rate at which cement hydrates.

Curing plays an important role on strength development and durability of concrete. Curing takes place immediately after concrete placing and finishing, and involves maintenance of desired moisture and temperature conditions, both at depth and near the surface, for extended periods of time. Properly cured concrete has an adequate amount of moisture for continued hydration and development of strength, volume stability, resistance to freezing and thawing, and abrasion and scaling resistance.

There are three basic ways of curing concrete.

1. The first - involves keeping the surface of the concrete moist by the use ponding, spraying/sprinkling, damp sand or damp hessian.

2. The second prevents the loss of moisture from the concrete by covering it with polythene sheeting or leaving the formwork in place.

3. The third involves the use of spray or roller applied curing compounds.