Concrete – (French beton), an artificial stone material made from rationally-tuned mix of binder (cement, bitumen, etc.), water (sometimes without), aggregates (sand, gravel, crushed stone, concrete block, etc.), and in some cases – special chemical additives (to improve the quality of the material). Concrete – one of the building materials. Concrete, it is called after molding and curing, before forming the mixture is called concrete. According to existing state standards concretes are divided by main destination, type of binder, aggregate form, structure and conditions of hardening. According to the primary use of concrete construction are (used for concrete and reinforced concrete load-bearing structures of buildings and structures), hydraulic (for construction of dams, locks, canal lining), concrete for walls of buildings and light covers, road (for traffic devices and airfield pavement), as well as special (heat resistant, chemically resistant, decorative, radiation-protective, insulating, polymer, betonopolimery and others). By type of binder concretes may be based on cementitious binders (for clinker cement – Portland cement, slag cement, slag cement and pozzolan, etc.), lime and slag binders (lime-sand, lime, slag, etc.), gypsum binders (at gypsum and gypsum-pozzolanic) special binders (for synthetic resins), the bitumen binder (asphalt). By type of aggregate cement can be dense, porous and special aggregates (these include natural sand (including river, sea and mountain), artificial sand (obtained by crushing the rocks, as well as dumping of metallurgical slag), gravel, crushed stone, concrete block). On the concrete structure can be: dense, porous, cellular, macroporous. Under the terms of hardening concrete are classified in hardening under natural conditions, in conditions of thermal treatment at atmospheric pressure, under heat and humidity treatment at a pressure above atmospheric pressure (autoclaved).