Nominal Mix
1- When the concrete is produced by taking standard arbitrary proportions of concrete ingredients, it is known as nominal mix concrete.
2- The nominal mix is a mix considering all ratio in the volume where Strength and cost of concrete and strength of concrete varies.
3- It is Prescriptive type concrete.
4- It is used in ordinary concrete involving concrete grade not higher than M20.
5- There is no quality control.
6- Water cement ratio is based on durability criteria, experience and practical trials.
7- Water content can be modified by slump value (field-based test)
8- No entrapped air content is considered.
9. Trial mixes concept is mentioned.
Design Mix
1-It can be defined as the process of selecting suitable ingredients of concrete and determining their relative proportions with the object of producing concrete of certain minimum strength and durability as economically as possible.
2- Design mix is a mix considering all ratio of mix is by weight where the strength of concrete is a constant cost of concrete can be reduced.
3- It is Performance-based concrete.
4- It is adopted for higher-grade concrete.
5- It has Quality control.
6- Water cement ratio based on concrete grade and 28 days compressive strength of concrete & durability of concrete.
7- Water content could be modified taking in to account the compaction factor value (laboratory-based test)
8- Entrapped air content considered according to nominal maximum size aggregates.
9- Not much consideration for trial mixes
