Mix design aims to achieve good quality concrete at site economically.
Quality concrete means
Better strength.
Better imperviousness and durability.
Dense and homogeneous concrete.
Economy
Economy in cement consumption
It is possible to save up to 15 % of cement for M20 grade of concrete with the help of concrete mix design. In fact higher the grade of concrete more are the savings. Lower cement content also results in lower heat of hydration and hence reduces shrinkage cracks
Best use of available materials
Site conditions often restrict the quality and quantity of ingredient materials. Concrete mix design offers a lot of flexibility on type of aggregates to be used in mix design. Mix design can give an economical solution based on the available materials if they meet the basic IS requirements. This can lead to saving in transportation costs from longer distances.
Other properties
Mix design can help us to achieve form finishes, high early strengths for early Deshuttering, concrete with better flexural strengths, concrete with pumpabllity and concrete with lower densities.