Concrete is a building material made of cement, aggregate (concrete aggregate) and water.
By adding concrete admixtures and additives to a concrete mixture, the workability and other concrete properties can be influenced.
The concrete building material is processed after mixing in the "liquid" state and can take any shape by using a 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 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