Water Reducing Agents are referred to as special chemical products that are added to a concrete admixture before it is poured for further processing. The main function of the water reducing agent is that it aids in the reduction of water quantity while the making of a concrete admixture.
Air-entraining agents have been regarded as essential for the workability of concrete since the 1930s, the uniform, stable tiny bubbles in concrete can improve the workability of concrete, reduce segregation and bleeding in fresh concrete, improve freeze-thaw durability and increase pump-ability of fresh concrete. A large number of chemical substances can be used as air-entraining agents of concrete. The most commonly used chemicals are abietic soap or sodium abietate, Vinsol resin, salts of fatty acids, salts of sulphonated hydrocarbon, K12, alkyl-benzyl sulphonates, triterpenoidsaponin, etc.
Compound admixtures are those ingredients in concrete other than portland cement, water, and aggregates that are added to the mixture immediately before or during mixing. The major reasons for using compound admixtures are: to reduce the cost of concrete construction; to achieve certain properties in concrete more effectively than by other means; to maintain the quality of concrete during the stages of mixing, transporting, placing, and curing in adverse weather conditions; to overcome certain emergencies during concreting operations.