Concrete is the most used building material in the world. Its ingredients are aggregates, water and cement as binding material. Cement is hydraulic: As soon as it is mixed with water, cement particles and water cristallize, which makes cement a hardening material.
Nowadays, concrete is not only produced out of these three ingredients, but contains mostly chemical admixtures and additives as well. With these ingredients, concrete gets more appropriate properties for different situations. Admixtures for example can help producing a more flowable concrete without using more water. The more water is in the concrete, the less strength and the more pores are there.
The cement in the concrete