To prepare a classic solution, the following raw materials are needed:
1. Cement is a binder that is the basis of a concrete mixture. It is a gray powder that crystallizes and hardens when moistened.
2. Construction sand. According to GOST 8736-93, sand is a free-flowing material, the size of grains of which should not exceed 0.5 mm.
3. Crushed stone is a mineral with grains of more than 5 mm, produced by crushing gravel, rocks or slag.
4. Ballast is a mixture of gravel and sand. The best for concrete production is a mixture with a ratio of 1: 3 (one part river sand to three fine gravel chips). This composition is sometimes referred to as "General Blend".
5. Water. For the manufacture of concrete mixture, only clean water without foreign inclusions is used. There are no clearly established rates of water consumption, since its costs are determined by the moisture content of other raw materials.
Concrete production includes the following stages:
Usually, operations for the preparation of raw materials - removal of contaminants, crushing of aggregates, are carried out at the enterprises that supply them for sale. In a concrete batching production plant, only special measures (preparation of chemical additives, cement grinding, heating of aggregates) are carried out when necessary. Since the performance of these operations entails additional costs for utility bills and the purchase of special equipment. These operations include: production of solutions of chemical additives, cement grinding, heating of aggregates in the cold season.