Concrete is a building material made of cement, aggregate (concrete aggregate) and water.
The addition of concrete admixtures and additives to the concrete mixture can influence the workability and other concrete properties.
Concrete as a building material is processed in a "liquid" state after mixing and can be formed into any desired shape using concrete formwork. This is referred to as the installation of fresh concrete, which consists of liquid cement paste and solid aggregate particles. In the course of the concrete hardening, most of the water contained is chemically bonded. The result is a solid building material, which is also known as artificial stone.
The concrete classification is based on the dry hardened density of the concrete:
- Lightweight concrete: γ < 2,000 kg/m3
- Normal concrete: 2,000 kg/m3 < γ < 2,600 kg/m3
- Heavy concrete: γ > 2,600 kg/m3