Chemical admixtures are the ingredients in concrete other than Portland cement, water, and aggregate that are added to the mix immediately before or during mixing. Producers use admixtures primarily to reduce the cost of concrete construction; to modify the properties of hardened concrete to ensure the quality of concrete during mixing, transporting, placing, and curing and to overcome certain emergencies during concrete operations.

Successful use of admixtures depends on the use of appropriate methods of batching and concreting. Most admixtures are supplied in ready-to-use liquid or powder form and are added to the concrete at the plant or at the jobsite. Certain admixtures, such as pigments, expansive agents, and pumping aids are used only in extremely small amounts & are usually batched by hand from pre-measured containers. Sometimes, effects such as mixing time, slump, change in temperatures are achieved through the addition of admixtures can be achieved by altering the concrete mixture-reducing the water cement ratio, adding additional cement, using a different type of cement, or changing the aggregate and aggregate gradation.

8+ Years

Functions:
An Indian Standards IS 9103 : 1999 (Reaffirmed 2004)

•   Water-reducing admixtures.
•   Retarding admixtures.
•   Accelerating admixtures.
•   Superplasticizing admixtures.
•   Viscosity modified admixture.
•   Corrosion inhabiting admixture & Air entraining admixtures.