What is concrete?
The general view is that concrete is something grey and solid, mainly used for the construction of foundations and ceilings. In fact, there are many types of concrete; they differ in structure, purpose and in appearance. We propose to talk about their diversity in more detail.
The usual cement concrete, which is most often used in suburban housing construction, looks grey and solid. The basis of it is cement, sand and water, taken in different proportions. Cement can be heavy, lightweight, cellular, silicate, polymer or gypsum.
One of the most used cement concretes is Portland cement. They account for approximately 65 percent of the total production.
Other types of concrete
Silicate concretes are prepared on the basis of lime, using an autoclave method of solidification. Gypsum concrete is made on the basis of gypsum and is used mainly for internal partitions, suspended ceilings and building finishing elements.
Many properties of concrete depend on its density. In terms of density, the concrete is divided into especially heavy with a density of more than 2500 kg per cubic meter, heavy (1800-2500 kg / m3), light (500-1800 kg / m3) and especially light (less than 500 kg / m3). Particularly heavy concretes are made on heavy aggregates – steel shavings or sawdust, iron ore or barite. In heavy concretes, rock is used as filler – granite, limestone, diabase. Porous aggregates are used in lightweight concrete: expanded clay, pumice, expanded slag; to particularly light include cellular concrete – aerated concrete, foam concrete, which are obtained by swelling the binding agent by special technology.
Heavy concrete goes to the foundations of houses; lighter concrete is used for internal walls. A regular construction plan clearly indicates the type of concrete to be used.
Strictly speaking, cellular concrete can no longer be considered an innovation: these building materials have long had their supporters, and their application in suburban housing construction has been expanding every year. But in comparison with traditional concrete, foam concrete and aerated concrete are still newer and more progressive materials.
Cellular concrete is a light material with very good thermal insulation characteristics, strong and durable. It can be finished with almost any material, including bricks and wood, it is very simple and cheap to transport. The use of cellular concrete blocks significantly reduces labour costs and accelerates the construction of the house.
The basis of foam concrete is a mixture of astringent and silica components with the addition of a foaming agent. After mixing with water, it swells, acquiring a cellular structure. As a result, we get a light material with very good thermal insulation characteristics. The ability to keep heat well is the main advantage of cellular concrete. For example, 20 cm of foam concrete in terms of heat savings corresponds to 40 cm of wood or 140 cm of bricks.
Foam concrete is manufactured both in stationary conditions and directly on the construction site, where by means of mobile equipment it is possible to obtain a composition of a given density.