Requirements of concrete mix design
The requirements which form the basis of selection and proportioning of mix ingredients are:
a) The minimum compressive strength required from structural consideration.
b) The adequate workability necessary for full compaction with the compacting equipment available.
c) Maximum water-cement ratio and/or maximum cement content to give adequate durability for the particular site conditions.
d) Maximum cement content to avoid shrinkage cracking due to temperature cycle in mass concrete.