First, what is the mechanism of sand?Mechanism sand is a kind of sand., mainly refers to the formed by sand crushing machine. What is the raw material of the mechanism sand? In general, as long as the hardness of the stone can be quite. Exactly when the compressive strength to meet the requirements of the igneous rocks, metamorphic rocks and sedimentary rocks. When water conservancy project construction area more in field, the mechanism of sand should first consider the use of local materials to save costs, if the combination of stonework excavation spoil is better. Used as a processing mechanism of sand of the parent rock, compressive strength shall comply with the provisions of GB / T14685 - 2001 the building of pebble and gravel ", namely the saturated compressive strength: igneous rocks should not be less than 80MPa, a metamorphic rock should not be less than 60MPa and sedimentary rock should not be less than 30 MPa.Mechanism of sand is relative to the river sand and other natural sand. The natural sand is the main forces of impact, such as sand, sand etc.. However, due to environmental protection and other reasons, the cost of natural sand is getting higher and higher, while its profit is getting lower and lower, and the market is getting smaller and smaller. So the mechanism is more and more popular with the market, the market share is also getting higher and higher!
Mechanism sand is artificial sand, is not the natural sand, with the sand pouring concrete is the mechanism of sand concrete.
Two, mechanism sand and natural sand contrast
With the natural sand is reducing day by day and protected by the policy, the mechanism of sand (that is, through the sand making machine, impact type crushing machine, and other professional sand making equipment crushed gravel materials) market has shown a great potential and vitality. Especially in recent years, the construction market demand is huge, and promote the rapid development of sand and gravel market. Using the mechanism of the production of high efficiency sand making machine, the unique advantages of the sand are gradually replacing the market, and become one of the best sources of building materials.
1, firmness and durability test. The strong performance of the mechanism sand is slightly worse than that of the river sand, but it still achieves the T GB/ 141684293 standard, and it is not a problem to use in the ordinary concrete. But in often suffer from impact friction of concrete components in use, in addition to must be mixed with additives, also should control concrete cement sand ratio and sand crushing index and the content of stone powder.
2, the mechanism of sand stone powder content on the properties of the cement mixture. Through the test of cement, mortar test, concrete test, machine-made sand used in the preparation of sand concrete and natural no big difference, generally speaking, under the same slump the premise, mechanism of sand water to slightly larger, but according to construction conditions and structures and transportation and other factors to consider. However, the strength of concrete is basically the same. The sand ratio should not be too high to prevent the concrete strength and durability of concrete.
3, the grain size of the mechanism is more irregular, in the use of cement and other structural bonding, often have better adhesion, more compression, the service life is longer.