Classified by apparent density
1. Heavy concrete. Concrete with an apparent density greater than 2600 kg/m3. Often formulated from barite and iron ore;
2. Ordinary concrete. The concrete density is from 1950 to 2500 kg/m3. Mainly made of sand, stone and cement, it is the most commonly used concrete type in civil engineering;
3. Light concrete. Concrete with an apparent density of less than 1950 kg/m3. Including light aggregate concrete, porous concrete and macroporous concrete.
Classified by quota
1. Ordinary concrete. Ordinary concrete is divided into: ordinary semi-dry hard concrete, ordinary pumped concrete and underwater poured concrete, each of which is divided into: gravel concrete and pebble concrete;
2. Antifreeze concrete. Antifreeze concrete is divided into: anti-freeze semi-dry hard concrete, anti-freeze pumping concrete, each of which is divided into: gravel concrete and pebble concrete.
Pumping concrete
The concrete of the mixture can be piped through a concrete pump.
It is required to have good fluidity. The aggregate particle size is generally not more than one quarter of the pipe diameter. It is necessary to add a pumping agent to prevent the concrete mixture from segregating and blocking in the pumping pipe, and to make the concrete mixture pumpable. Admixtures that are smoothly passed through, water reducing agents, plasticizers, air entraining agents, and thickeners can be used as pumping agents. Adding appropriate amount of mixed materials (such as fly ash, etc.) can avoid delamination, bleeding and blockage of the conveying pipeline during concrete construction.
Among the raw materials for pumping concrete, coarse aggregates should be preferred (pebble).
Commodity concrete
Commodity concrete refers to concrete that is produced in a factory and sold as a commodity. Compared with on-site mixing concrete, commercial concrete is produced by professional production enterprises, most of which are equipped with advanced production equipment, accurate measurement, uniform mixing and high quality. There is a complete quality inspection system to ensure quality. The purchase of commercial concrete by construction enterprises can reduce the stacking of on-site building materials, which is conducive to environmental protection and civilized construction. Specific specifications are further divided into C15, C20, C25, C30 and so on.
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