How is crushed stone classified by brand?
Despite the technical progress and the emergence of new technologies, there is material that has not undergone any changes and is used, as before, only the equipment for working with it is being improved. Crushed stone is a loose material of artificial or natural origin, obtained with the help of rock crushing technology, which are distinguished by high hardness.
For the production of concrete with increased compressive strength, rubble from high-strength rocks, such as granite, is used for the production of plasters and various concrete products, natural crushed stone of reduced strength - dolomite, limestone.
The grade of crushed stone for strength is formed by its resistance to crushing, abrasion and compression. Tests are carried out in a special experimental drum. These impacts are similar in strength to crushed stone loads in the operation of road surfaces or construction work.
It is marked as follows:
- M1200-M1400 - crushed stone high-strength, where the content of weak rocks should not exceed 5%;
- M800-M1200 - strong, the content of grains of weak rocks does not exceed 10%;
- crushed stone M600-M800 has an average strength;
- M300-M600 - crushed stone of weak strength;
- below M300 - very weak strength, which can contain up to 15% of such grains in its composition.
Which crushed stone will provide us with strength?
Rubble M1000 is a strong enough material. Like the M1400-M1200, it is used for the construction of railroad tracks and highways, in the production of reinforced concrete products, concrete mixtures. This brand of rubble has increased frost resistance, that is, it carries more than three hundred freeze-thaw cycles. Products made of this material will differ in strength, durability and durability.
Rubble grade 800 is characterized by roughness of the surface, which plays a decisive role in increasing adhesion to cement and other components in the manufacture of concrete mixes. This brand has a high resistance to low temperatures, high humidity, and also resistance to chemical and physical influences.
Crushed stone M800 from granite, which means it has a rather high strength. It is obtained by crushing stone rock and further sieving. Used for exterior finishing works, ennobling the territory, strengthening the foundation and so on.
Weak grades of crushed stone
Crushed grade 600 is extracted by open method in lime quarries, that is, drilling and blasting technologies and further processing of rock are used. Used for road construction and reinforced concrete products.
Features frost resistance, water saturation and water absorption. Because this material is calcareous, dense ramming occurs, and this helps to avoid the formation of negative voids in concrete mixtures.
This brand of rubble is much cheaper than granite variants, but in terms of its qualities and properties, it is not much inferior. In addition, it is environmentally friendly material. If there is no opportunity to buy more expensive granite material, it is worth paying attention to the lime, which has high physicochemical characteristics.
Rubble M400 is widely distributed. Characterized by weak strength and low frost resistance, but these qualities do not affect the performance of works in which lime material is used. It is used mainly as a pillow or a ballast layer for asphalt concrete pavements.
Rubble M200 of very weak strength is used for construction of roads with low intensity, as well as for finishing works. This brand is perhaps the cheapest and, unfortunately for it, is not in demand, since the intensity of life is now almost everywhere quite high, and requires reliable materials.