As we know concrete is a mixture of cement, sand, aggregate, and water, and this component proportion is called the mix ratio of concrete. The mix ratio of concrete determines the grade of concrete. Concrete grades are of many types but the mix ratio of concrete is classified into three types. If you want to know about types of concrete mix ratio and their strength in details then you shloud read this article carefuly.
Types of concrete mix ratio
Generally concrete mix ratio is of three types:
- Nominal Concrete mix ratio
- Standard concrete mix ratio
- Designed concrete mix ratio
Nominal concrete mix ratio
Nominal concrete mix ratio has fix proportion mix ratio. Its compressive strenght is lower than standard mix ratio. Except M20 grade concrete, Nominal mix ratio of concrete do not use in heavy construction and it is not suitable concrete for any load bearing structure. M20 grade concrete is the only concrete coming from the nominal mix ratio that can be used for load bearing structures. M5, M7.5, M10, M15, and M20 grade concrete come under nominal mix ratio.
This chart shows compressive strength of concrete after 28 days of pouring.
Normal mix ratio chart
| Concrete grade | Mix ratio | Compressive strength (psi) | Compressive strength (MPa) |
|---|---|---|---|
| M5 | 1:5:10 | 725 psi | 5 MPa |
| M7.5 | 1:4:8 | 1087 psi | 7.5 MPa |
| M10 | 1:3:6 | 1450 psi | 10 MPa |
| M15 | 1:2:4 | 2175 psi | 15 MPa |
| M20 | 1:1.5:3 | 2900 psi | 20 MPa |
Standard concrete mix ratio
Standard concrete mix ratio has more compressive strenght than the nominal mix ratio concrete. In Standard mix ratio concrete only M25 grade concrete have a fix mix ratio of material.
This chart shows compressive strength of concrete after 28 days of pouring.
Standard mix ratio chart
| Concrete grade | Mix ratio | Compressive strength (psi) | Compressive strength (MPa) |
|---|---|---|---|
| M25 | 1:1:2 | 3625 psi | 25 MPa |
| M30 | Design mix | 4350 psi | 30 MPa |
| M35 | Design mix | 5075 psi | 35 MPa |
| M40 | Design mix | 5800 psi | 40 MPa |
| M45 | Design mix | 6525 psi | 45 MPa |
Designed concrete mix ratio
Designed mix ratio of concrete do not have fix proportion of material its mix ratio propotion designed by the professionals. You can achive any desiralbe strength of concrete by using Designes concrete mix ratio. By using such type concrete, some additives, and admixture it is possible to achive desirable setting time/ compressive strength and workbility of concrete.
This chart shows compressive strength of concrete after 28 days of pouring.
Designed mix ratio chart
| Concrete grade | Mix ratio | Compressive strength (psi) | Compressive strength (MPa) |
|---|---|---|---|
| M50 | Design mix | 7250 psi | 50 MPa |
| M55 | Design mix | 7975 psi | 55 MPa |
| M60 | Design mix | 8700 psi | 60 MPa |
| M65 | Design mix | 9425 psi | 65 MPa |
| M70 | Design mix | 10150 psi | 70 MPa |