Objectives and methods of Concrete Mix Design

Objective :

Concrete of different qualities can be obtained by using its constituents namely, cement, water, fine and coarse aggregates, and mineral additives, in different proportions. This proportions should indicate whether it is by volume or by mass. The water-cement ratio is generally expressed by mass. The amount of entrained air in concrete is expressed as a percentage of the volume of concrete. The amount of admixture is expressed relative to the weight of cement. The wide use of concrete as a construction material has led to the use of mixes of fixed proportions which ensure adequate strength. These mixes are known as a nominal mix. It may be used for concrete of grade M20 or lower.

Methods of Concrete Mix Design  :

1)Trial and adjustment method of mix design.

2)British DOE mix design method.

3)ACI mix design method.

4)A rapid method for mix design.

5)Mix design according to Indian Standard Recommended Guidelines.