Building material, such as gravel and sand, is a by-product of the extraction of natural granite. In addition, it can form as a result of weathering of rock. In fact, this is a combination of sand and gravel, widely used in construction.
In general, building material is granite and limestone rock waste generated during mining and processing, which contains rubble fragments and quarry sand.
When crushed in a sorting factory, the mixture undergoes screening , grinding to fractions, cleaning of small debris, as a result, different types of building material are obtained based on the size of grains of gravel.
If 4% or more clay and dust are present, the product cannot comply with GOST 25607-94. In addition, it is required that the radioactive background be within 300 Bq / kg, which is considered safe and allows the mixture to be used in the construction of residential buildings.
The main characteristics that you need to know when laying and transporting:
- volume weight;
- bulk density.
It turns out that not only the grain composition is important, but also the density, that is, the compaction coefficient of crushed stone, characterizing the change in its volume during tamping, as well as shrinkage and transportation. One of the most popular sizes of the fraction is 20-40 mm, it is a mixture of C6 with a bulk weight of 1.35 t / m3. With a larger fraction, tamping is less effective.
The shape of the grains also plays a role, preferably when it is cuboid. Actually, these indicators determine the quality of the building material. If you ignore it, it is hardly possible to achieve good operational characteristics of the pavement, for which, in most cases, crushed-sand mixture is used.
The advantages of bulk mixtures
Crushed-sand mixtures of various types are durable materials that make it possible to use them when conducting outdoor work.
- ability to absorb water vapor;
- resistance to high humidity;
- immunity to low temperatures;
- safe class of radioactivity;
- strength, wear resistance under high loads;
- optimal drainage filtration coefficient in coatings for various purposes;
- granular composition of crushed stone and sand.
These are important manufacturing qualities of bulk products, which are also distinguished by their low cost.
Types of material
The crushed-sand mixture, being a product of crushing, has different grain sizes, which determines its fraction. The scope of the material depends on this parameter.
- ЩПС С1 - a mixture having a grain size of 40 mm. In fact, the product may include fractions from 5 to 10 mm, which occupy most of the volume, the largest are present in an amount of 10% of the total, the composition also allows the presence of 10% of dusty microparticles. The main field of application of the C1 mixture is considered to be the arrangement of pavements, in particular, when it is required to obtain a perfectly flat, smooth surface. With the help of the material, even non-asphalt roads can be erected. These are mainly landing strips of airfields.
- The C2 mixture has high strength properties, it includes crushed stone with frost-resistant properties (F100 or F300). The maximum size of the constituent grains is 20 mm, and granular fractions of about 10 mm in size are at the core. Clays and dusty particles are only 5%. The material has its advantages, including the possibility of laying under any weather conditions and temperature.
The coating obtained with this product is not afraid of humidity, cold, and is not subject to cracking during operation. It can be used both for creating coatings of category I-III, and for landscaping in private areas, due to its affordable cost.
- C3 products are distinguished by the largest pellets with a size of 120 mm. Its components are granite crushed stone and quarry sand, while dust and clay do not exceed 4% according to GOST. This is a durable, frost-resistant material, the laying of which is simpler and easier, in comparison with other types of ShchPS. The main purpose is additional layers of the road surface, which make it possible to reduce the cost of materials such as asphalt, concrete.
Granite fractions have good compressibility, for this reason the coatings are resistant to increased loads.
- ShchPS PS4 includes sifted quarry sand and crushed stone granules with a fraction of 80 mm. The mixture is used for residential construction, since the radiation performance of the product does not exceed 300 Bq / kg. This is a quality material, convenient for storage and transportation, you can work with it in any climatic conditions. It is used to create automobile road surfaces, ballast prism of railway and tram tracks, strengthen roadsides.
- The C5 mixture has a fraction of 40 to 80 mm. This is a high-quality bulk product that is in high demand, the bulk of which are particles with a size of 40-60 mm with the amount of dust-like additives not more than 4%. The scope of use of the product is similar to the use of C4, it is also used in the construction of residential and industrial buildings, road surfaces, for concrete work, as reinforcing layers of curbs.
The scope of mixtures C4 and C5 is more extensive, they are considered the most popular materials.
- C6 gravel and sand composition differs from other bulk mixtures in optimal tamping by roller, long-term storage, and the ability to work at critical temperatures and in different weather conditions. The basis of the material is granite fractions from 5 to 20 and 20-40 mm. It is used in almost all areas of construction. After laying, movement on the created coating is permissible almost immediately. The mixture has a low price, which makes it possible to save on asphalt and concrete.
- Products C7 and C8 mainly serve when laying the bottom layer of roads and are distinguished by a small fraction of 10 and 5 mm. The cement reinforcement of the C7 material makes the mixture more resistant to low temperatures and eliminates the appearance of cracks on the coating during operation.
- The C9 mixture has a granule size of 80 mm, in addition to road surfaces, it is used for the construction of parking lots, squares, sidewalks and country roads.
- At the initial stages of road construction, the use of C10 with particles of 20 mm is allowed, up to 30% of quarry sand and 20% of clay and dust are present in its composition.
Based on the high quality characteristics of compaction of the material, the most popular is the gravel-sand mixture C4, which is also considered the closest to natural minerals in composition.
In the next video, you can find out how to get S5 ShchPS and what are its main advantages.