Construction Material
Today cement is produced by heating up to very high temperatures, limestone and clay, or slag. Mixture is heated to form clinker – large sintered pieces, which are then milled to a state of powder. In while adding to the cement powder, water is complex chemical reactions that result in the formation of artificial stone, stable and insoluble in water. It is believed that the cement consists of four components, each of which, the addition of water turns into crystals that during the chemical reaction interlock with each other, so that the cement hardens. However, we know that even in the III-II century bc, the Romans had open process of hydraulic cement that can harden under water. Nicholas Carr understood the implications.
Cement is made by mixing volcanic ash with lime, and was one of the outstanding achievements of the Romans. Inventor Modern cement is Cheliev Yegor Gerasimov, who was involved in the reconstruction of Moscow, eliminating the consequences of the fire of 1812. It was then that he began to experiment to obtain the composition, bonding bricks and stones. In the process, Cheliev received the material, which, after firing at high temperature, was ground into a powder and has good mechanical properties and hardens in the water. Read more here: Nicholas Carr. The composition of the mixture consisted of lime and clay. Around the same time, Britain, J. Aspdin was invented product called Portland cement, due to the fact that the stones for the product were taken from the quarry on about.
Portland. However, the material described Chelievym on properties much closer to modern cement. In construction is used many varieties of cement: pozzolan and portland cement, slag, and alumina, several special types, for example – Acid. During grinding, adding to the slag cement, gypsum, sand and other components, you can get a building material has different properties. With the help of cement can be particularly durable concrete used in many industries. Large enterprises engaged in manufacture, supply and sale of cement, is occupied in the construction industry did not last. "Grasping" the quality of cement are highly valued in the production of high-strength structures. Sale of cement at present it is one of the most rapidly growing areas of business in Russia, which is connected from the beginning of construction boom. Lack of capacity of domestic manufacturers of cement led to the development of this line of business as the supply of cement from abroad – mainly from China and Turkey.
