Classification of concrete chemical admixtures

There are many types of chemical admixtures for concrete. Each admixture often has one or more functions, and its chemical composition can be organic matter, inorganic matter, or a complex of both. Therefore, there are different classification methods for concrete chemical admixtures.
1. Classified by main function
(1) Chemical admixtures that improve the rheological properties of concrete mixtures. Including various water reducing agents, air entraining agents and pumping agents, etc.
(2) Chemical admixtures that adjust the setting time and hardening properties of concrete. Including retarder, early strength agent and accelerating agent.
(3) Chemical admixtures that improve the durability of concrete. Including air-entraining agents, antifreeze agents, waterproofing agents and rust inhibitors, etc.
(4) Chemical admixtures that improve other properties of concrete. Including air-entraining agents, expanding agents, colorants, etc.
Concrete chemical admixtures are classified according to their main functions, which have the advantages of being concise and applicable, and also comply with the naming principle. When a certain admixture (mainly compound admixture) has more than one main function, it is named according to more than one of its functions. For example, when a certain admixture has water-reducing and early-strength effects, it is called early-strength water-reducing agent; when a certain admixture has water-reducing and air-entraining effects, it is called air-entraining water-reducing agent, etc.
2. Classification by chemical composition
(1) Inorganic chemical admixtures. Including various inorganic salts, some metal elements and a small amount of hydroxides, such as CaCl2 and NaSO4 in early strength agents, aluminum powder in air-entraining agents, aluminum hydroxide in waterproofing agents, etc.
(2) Organic chemical admixtures. This type of admixture accounts for the vast majority of concrete admixtures, and there are many types. Most of them belong to the category of surfactants, including anionic, cationic, nonionic and polymeric surfactants. Such as lignin sulfonate, lignin sulfonate formaldehyde condensate, etc. in water reducing agents. Some organic chemical admixtures themselves do not have surface activity, but they can be used as high-quality admixtures.
(3) Composite chemical admixtures. Admixtures made of appropriate inorganic and organic compounds often have multiple functions or significantly improve certain properties. This is also the embodiment of "hybrid advantage" in admixture technology and is one of the development directions of admixtures.
Concrete chemical admixtures are classified according to their ingredients, which is conducive to the development of scientific research and the development of new varieties.