- Crushed stone designationBuilding
- Breed of crushed stoneGravelly
- Gravel formFractionated
Crushed stone gravel — a product of crushing of rocks and stone materials in the form of pieces (usually angular form), fractions 5x20 and 20x40. Crushed stone is applied as filler by production of concrete goods of products, in construction of highways and hydraulic engineering constructions.
From all natural stone materials used in construction, crushed stone is the basic. Crushed stone as nonmetallic material is applied:
• for construction, reconstruction, repair and the maintenance of highways
• as a filler it is used for preparation of asphalt concrete mixes for the top coat layers (fraction of 5-20 mm)
• as a bed for railway tracks in the railway industry
• as large filler by production of paving slabs
Fractions of crushed stone:
On fineness crushed stone is divided into fractions. The fraction is the most admissible size of separately taken stone (grain). Divide the main and accompanying fractions of crushed stone. Treat the main fractions: the 5-10th, 5-20th, 10-20th, 20-40th, 20-65th, 25-60th, 40-70th. Treat the accompanying fractions: the 0-2nd, 0-5th, 0-15th, 0-20th, 0-40th, 0-60th, 2-5th.
The Ozentas company makes crushed stone of two main fractions of 5-10 mm, 10-20 mm.
Crushed stone from gravel has to contain shredded grains in number of not less than 80% on weight.
The form of grains of crushed stone and gravel is characterized by the content of grains of a lamellar (leshchadny) and iglovaty form.
Crushed stone depending on the content of grains of a lamellar and iglovaty form is subdivided into 5 groups.
Durability of crushed stone and gravel is characterized by the brand determined by a drobimost of crushed stone (gravel) at compression (crush) in the cylinder. These indicators imitate resistance of stone material at influence of the vehicles passing on the road and mechanical influences in the course of construction of road designs (laying and consolidation by skating rinks).
Frost resistance of crushed stone and gravel is characterized by number of cycles of freezing and thawing at which losses as a percentage on the mass of crushed stone and gravel do not exceed the established values. It is allowed to estimate frost resistance of crushed stone and gravel on number of cycles of saturation in solution of sulfate sodium and drying. On frost resistance crushed stone is subdivided into brands: F15; F25; F50; F100; F150; F200; F300; F400.