#TipTuesday: Concrete Curing

#TipTuesday.

Concrete Curing could be defined in different ways but it in simple terms, it is letting concrete grow into its full potential by keeping it moist and at the right temperature so that the cement can hydrate.

1) When concrete is initially placed — it must be kept warm, but not too warm.

All of the concrete needs to be treated with care but usually there’s plenty of moisture inside — it’s the surfaces that are most at risk.

2) Drying of the concrete surface can result in crazing and plastic shrinkage cracks. It also makes the concrete more porous (higher permeability) — again, especially at the surface.

3) Initial curing keeps the concrete surface from drying out before the concrete sets — usually only needed in dry, windy conditions. This is done by fogging or spraying on an evaporation retarder. This is followed by final curing to keep the surface from drying for several days while it gets stronger.

4) There are two ways to cure a concrete surface: Keep it damp or prevent it from drying out. To keep the surface damp, it can be misted with water or covered with curing blankets — some of the newer ones are very similar to a wet disposable diaper. This way of curing is ideal and has the advantage of leaving no residue on the surface.

5) The more common way to cure the surface is to spray on a curing compound that forms a thin membrane to prevent the moisture in the concrete from evaporating. This is sort of like putting the concrete inside a balloon and since there’s usually plenty of moisture in the wet concrete, as long as it can’t dry out, it will cure.

6) When we get the curing right, the surface will reach its full potential of strength and durability.