At The Conco Companies, we have experience placing any type of concrete for a broad range of projects and in a variety of weather conditions. Our crews use several different methods for curing concrete as it is determined by the type of construction and the concrete mix as well as outside temperatures and humidity. Other considerations include project specifications and/or parameters of the jobsite. However regardless of the technique used for curing, it is important to keep the concrete moist and prevent further loss of moisture.
The Portland Cement Association explains that the purpose of curing is to provide the “adequate amount of moisture for continued hydration and development of strength, volume stability, resistance to freezing and thawing, and abrasion and scaling resistance.” When we control the rate and amount of moisture the concrete loses during cement hydration, it is allowed to achieve its optimal strength and durability.
Curing is done at the jobsite once the concrete is placed and finished, or during the manufacturing of concrete products. While curing may only take a few days, the concrete requires a number of days or in some cases weeks or months to attain its full strength and durability.
Preventing the loss of moisture during curing is done in a number of ways. One method leaves the formwork in place and/or covers the concrete with an impervious paper, plastic sheeting or a membrane-forming compound. Another includes spraying (or fogging), ponding or using wet coverings to cool the concrete as the water evaporates.
The American Concrete Institute (ACI) recommends a curing period of a minimum of 7 days or until 70% of the specified compressive strength is achieved for most concrete structures in temperatures 40º F and above. If desired an accelerant can be used to speed up the hardening process and reduce the curing period to only 3 days if temperatures are above 50º F. Other variables are determined by the size and shape of the structure and strength requirements as well as the type of weather conditions the concrete will be exposed to during its life-cycle.
The Conco Companies are one of the leading concrete contractors in the Western U.S. and offer a wide range of quality services and products. Our experience includes providing services for commercial, educational, parking and other construction development as well as public works projects. We serve California, Washington State, Oregon, Colorado and Nevada.
Source: cement.org/for-concrete-books-learning/concrete-technology/concrete-construction/curing-in-construction, concrete.org/TopicsinConcrete/TopicDetail.aspx?id=25&Search=Curing