We use different grades of concrete for different parts of the building.
We could say the grade of concrete is the only thing we do care lot while concreting.
In this post, we are going to explain that in detail.
Grades of Concrete
Actually, what do we mean by grade of concrete.?
Concrete grades are denoted by M10, M20, M30 according to their compressive strength.
The “M” denotes Mix design of concrete followed by the compressive strength number in N/mm2
“Mix” is the respective ingredient proportions which are Cement: Sand: Aggregate Or Cement: Fine Aggregate: Coarse Aggregate.
we already discussed the mix design here.
If we mention M10 concrete, it means that the concrete has 10 N/mm2 characteristic compressive strength at 28 days.
Note
The Minimum grade of concrete for Plain Cement Concrete (PCC) is M15
The Minimum grade of concrete for Reinforced Cement Concrete (RCC) is M20
Concrete Grade and Mix Ratio Table
As per IS 456:2000, the grades less than M20 should not be used in RCC works
Group | Concrete Grade | Mix Ratio | Characteristic Compressive Strength (N/mm2) |
Ordinary Concrete | M5 | 1 : 5 : 10 | 5 N/mm^{2} |
M7.5 | 1 : 4 : 8 | 7.5 N/mm^{2} | |
M10 | 1 : 3 : 6 | 10 N/mm^{2} | |
M15 | 1 : 2 : 4 | 15 N/mm^{2} | |
M20 | 1 : 1.5 : 3 | 20 N/mm^{2} | |
Standard Concrete | M25 | 1 : 1 : 2 | 25 N/mm^{2} |
M30 | Design Mix | 30 N/mm^{2} | |
M35 | Design Mix | 35 N/mm^{2} | |
M40 | Design Mix | 40 N/mm^{2} | |
M45 | Design Mix | 45 N/mm^{2} | |
M50 | Design Mix | 50 N/mm^{2} | |
High Strength Concrete | M55 | Design Mix | 55 N/mm^{2} |
M60 | Design Mix | 60 N/mm^{2} | |
M65 | Design Mix | 65 N/mm^{2} | |
M70 | Design Mix | 70 N/mm^{2} |
Hope you learned something useful. Support us by Sharing.
Happy Learning 🙂