Rubble

Crushed Stone - is a loose, free-flowing material from the small stones of irregular shape, depending on the size of the particles, opredelyaetsyafraktsiya rubble. Particles smaller than 3 mm is used as the sand. The smaller the number the smaller faction of rubble stones are included in it. Large fractions of crushed stone for concrete boleeprochny grasping, and fine fractions of crushed stone, respectively, better than filling a cavity of all kinds. Crushed various factions. obtained by crushing larger pieces of solid rock. Used to prepare the solution of concrete as coarse aggregate. Thanks to the acute-angled shape poverhnostschebnya rough, so the gravel excellent adhesion to a cement-sand mortar in the manufacture of concrete. What is gravel? Crushed granite - rubble, which is obtained by crushing natural granite. When mined granite rubble, he is a solid monolithic rock. It should blow up, and then the resulting explosion blocks in detail in a crushing machine. The final operation is the sifting of rubble at the faction. With decreasing fraction of rubble, increasing its cost. Crushed isolated in three groups zavisimostiot size fragments: - rubble large 50-100 mm - rubble average 25-50 mm - 10-25 mm fine gravel. Crushed gravel - rubble obtained by two methods: the first option involves sifting quarry rock, and the second crushing natural rock cliffs. Such rubble less durable than granite rubble, gravel and crushed stone advantage but there are also advantages - the radioactive background of this rubble is usually very low. Gravel chippings sfraktsiey 3-10 mm, often used as decorative material. Crushed limestone (dolomite) - after the crushing of limestone and subsequent chemical processing of the limestone rubble. Dolomite of all kinds is the cheapest form of rubble. But the downside to this is the rapid erosion of gravel, crushed limestone so infrequently used. Crushed limestone is a ton stones or white depending on the impurities (clay, silica, iron oxide), yellow, gray, reddish brown, and others such gravel has a high impact resistance, resistance to temperature changes, eco-friendly material. Characteristics of rubble: Used rubble has many characteristics because of differences in the rubble of independent and quality of product and price it accordingly. In the rubble normiruyuetsya content of grains of lamellar and needle shapes. By the rubble of the form are the particle thickness or width is less than the length of three times or more. The shape of the particles rubble divided into three groups (in percentage terms by% weight): - cuboid - 15 - improved from 15 to 25, - usually from 25 to 35. You should know that a mixture of grains of crushed stone cubic form gives the most dense packing, and cubiform grains are more durable than the plate and needle rubble. Another characteristic of the rubble is a strength, namely the strength of rock in compression under certain conditions. Determining divisibility. gravel in the cylinder, gravel is assigned brand. Depending on the type of gravel is divided into the following groups: - very strong - 1200-1400 - durable - 1200-800 - Medium Strength - 800-600 - weak - 600-300 - very light - 200. Generally gravel marks on the strength of 1400, 1200, 1000 does not contain grains of soft rock of more than 5%, gravel marks 800, 600, 400 - more than 10%, gravel marks 300 and 200 - more than 15% by weight. Also in the rubble of standardized content of dust and clay particles with very small size (less than 0.05 mm). For all types and brands of rubble on the strength of clay content in lumps in the total amount of dust and clay particles should not exceed 0,25% by weight. We can not ignore such a feature such as frost, because the gravel is most commonly used for external work. Thus, frost rubble characterized by the number of cycles of freezing and thawing. By frost rubble divided into grades. In this case the rubble of crushed grain should contain no less than 80% by weight.