Hot concreting refers to laying concrete when the ambient temperature is hot, such as during the summer. Such high temperatures make the concrete mixture lose its water content quickly to the extent that it can start cracking when it has not yet cured. To prevent this early deterioration, contractors use several methods to make the concrete cure at a normal pace (not accelerated by high temperature). This article discusses the different ways through which water can be used to cure concrete.
Ponding
This method is ideal for curing flat surfaces onto which concrete has been laid such as floors and flat roofs. In this method, a dyke is constructed on the outer edge of the concrete surface. The dyke is then filled with water so that a shallow pond is formed. This pond must be constantly monitored to ensure that the water does not dry up until after several days when the concrete has cured. Ponding is a very common method of curing concrete because of how easy it is to set up.
Sprinkling, Mist Curing or Fogging
In this method, water in the form of mist is sprayed onto the concrete surface so that its temperature is kept low. It is essential to prevent the temperature of newly poured concrete from increasing since high temperatures accelerate the rate at which the concrete loses moisture from its surface, thereby cracking. As the concrete surface is sprinkled with water, it remains cool and retains its moisture, thereby curing effectively. This method is very good for surfaces that are not flat, such as sloped roofs.
Wet Coverings
Another way to cure cement is to cover it with materials that are water absorbent, such as burlaps, hessian or cotton mats. These coverings must be kept moist so that they do not absorb water from the freshly poured concrete via capillary action (movement of water from the cement to the covering that has lost its moisture content). The wet coverings can be kept wet by sprinkling water over them. This will take less water than the sprinkler method above but it is more labor intensive since care must be taken to ensure that the entire covering is kept uniformly moist.
It is the duty of the contractor, someone like Armstrong Creek Concreting & Outdoor Constructions, to ensure that the concrete cures well. However, it is also important for you the owner of the home or project to have adequate knowledge about how concreting is done so that you can effectively supervise the contractor. Use the information above to guide you as you play that supervisory role.