Superplasticizers, also known as high range water reducers are used as dispersants to avoid particle aggregation, and to improve the flow characteristics -the rheology – of suspensions such as in concrete. Their addition to concrete or mortar allows the reduction of the water to cement ratio, not affecting the workability of the mixture, and enables the production of self-consolidating concrete and high performance concrete. This effect drastically improves the performance of the hardening fresh paste and the resulting hardened concrete.
Superplasticizers, reduce water content by 20 to 30 percent and can be added to concrete with a low-to-normal slump and water-cement ratio to make high-slump flowing concrete. Flowing concrete is a highly fluid but workable concrete that can be placed with little or no vibration or compaction.