Superplasticisers are high range water reducing admixtures..Admixture is defined as a material other than cement ,water and aggregate that is used as an ingredient of concrete and is added to the batch immediately before or during mixing. The development of superplasticisers is one the major break throughs in concrete technology, which will have a significant effect on the production and use of concrete in the next millennium. Superplasticisers have been greatly responsible for development of the following connects.
1) High performance connects
2) High strength concrete
3) High durability concrete
4) Self compacting concrete
5) High volume flyash /slag concrete
6) Fibre reinforced concrete
7) Anti washout concrete under water.
A superplasticiser is one of a class of admixtures called water reducers that are use to lower the mix water requirement of the concrete. They are chemically different from normal water reducers and are capable of reducing water contents by about 30 percent. They are variously known as superplasticisers, super fluidizers , superfluidifiers, super water reducers or high range water reducers. In Japan, during the late 1960’s superplasticisers were developed. Ready mix concrete incorporating water reducers and workability enchancers make use of superplasticisers and delivers increased workability without loss of ultimate strength or durability. The role of superplasticisers in ready mix concrete industry is essential where ordinary as well as high strength or high performance concrete with slump retention capability are to be produced. Superplasticisers can be used to reduce the amount of water to produce high strength concrete and to reduce the amount of cement.