Granite crushed stone is fragments of rocks having an acute-angled shape. The material is formed as a result of natural weathering, and it consists of loose and weakly cemented clusters. Debris can have sizes up to 100 mm, and according to the degree of fineness are divided into several fractions:
- 0-5 mm are used for interior decoration, arrangement of paths and sports grounds,
- 5-20 mm is crushed stone of fine screening, intended for the preparation of concrete and structures from it. It is used to equip the foundations, as well as supports for the bridge and canvas, covering roads and runways,
- 20-40 mm is crushed stone, which is fragments of medium size. It is used to create canvas for cars and railway transport, as well as in laying the foundations of industrial facilities,
- 40-70 mm - this fraction is typical for large-sized material, it is used in the manufacture of concrete, as well as large-sized structures and production facilities.
Mining is carried out in a quarry way: first, granite is blown up, and the lumps formed during the explosion are crushed. Grinding is carried out using special equipment, which is located in crushing and screening complexes. The resulting fragments are sieved and divided into various fractions. At the same time, the smallest fraction is the most expensive in price.
differs in strength, frost resistance, flakiness (that is, determining the shape of debris from the point of view of the plane of their shape) and radioactivity. The compacting density of the material will depend on what the flakiness indicators are.
Resistance to high temperatures depends on the number of freezing and further defrosting cycles. Strength characterizes crushed stone as resistant to mechanical stresses on grains (crushing ability, wear, compaction are checked). There are several strength groups:
- high is marked M1200-1400,
-strong - M800-1200,
- medium strength - M600-800,
- weak strength - M300-600,
- very weak (M200).
As a rule, the choice of brand of this natural material is determined by the degree of radioactivity. Suitability for use should be confirmed by mandatory certification and conclusions of sanitary and epidemiological institutions.
The structure of crushed granite contains spar, mica and quartz, the combination of which determines resistance to temperature extremes.
The scope of granite crushed stone is wide enough:
- in finishing works due to different shades of rubble,
- in laying tracks
- in the creation of concrete and reinforced concrete products,
- in the arrangement of the foundation of buildings,
- in the construction and repair of highways and railways,
- the smallest fraction is used for landscaping and decoration of buildings.
The cost of granite crushed stone depends on its fraction - the smaller the fraction, the more expensive the price of a cubic meter of material. The average cost of a small fraction is 2200 rubles per cubic meter, and a large fraction - 2000 rubles.