What Is the Grade of Concrete?
Grades of concrete are defined by the concrete mix proportion and the minimum strength of concrete at end of 28 days curing period.
The Concrete Grade is can be known by calculating the compressive strength of concrete in Mpa, where M stands for mix and the MPa denotes the overall strength
There are different types of concrete mix which are based on concrete classification according to its compressive strength.
For making concrete we use cement, sand, aggregate, and water which are mixed with a certain ratio, and concrete is cast and put in a cube of 150 mm size and put in a water bath for 28 days and afterward, it is tested in a compression testing machine. The compressive stress result is known as the “grade of concrete“. It is expressed in N/mm²
The concrete grade is denoted by M10, M20, M30, and so on according to their compressive strength.
Concrete Grade As Per Indian Standards
The “M” refers to Mix and Number after M (M10, M20) Indicating the compressive strength of concrete after 28 days of curing and testing.
M indicates the proportion of materials like Cement: Sand: Aggregate (1:2:4) or Cement: Fine Aggregate: Coarse Aggregate.
If we mention M10 concrete, it means that the concrete has 10 N/mm2 characteristic compressive strength at 28 days.
In the designation of concrete mix M to the mix and the number to the specified compressive strength of 150 mm size cube at 28 days, expressed in N/mm^2.
Concrete Grade Per British/European standards
As per BS 8500-2 British/European standards, the grade of concrete is denoted as C10, C15, C20, C25, etc., ‘C’ which means ‘Concrete Strength class’, and the number behind C refers to characteristic Compressive strength of Concrete in N/mm2 @ 28 days when tested with the 15 cm dia. & 30 cm height cylinder in a direct compression test.
The grade of concrete is also denoted as C16/20, C20/25, C25/30, etc., which means Concrete Strength Class (C) the number behind C refers to the Compressive strength of Concrete in N/mm2 when tested with Cylinder / Cube.
Different mix proportions of the materials used to make concrete namely
- Coarse aggregate
- Fine aggregate
Resulting in concretes with different properties.
Following are the Standard Concrete Grade with their Mix Proportions and Strength
|Grades of Concrete||Mix Ratio (Cement: Sand: Aggregates)||Compressive Strength|
|Lower Grade of Concrete|
|M5||1: 5:10||5 MPa||725 psi|
|M7.5||1: 4: 8||7.5 MPa||1087 psi|
|M10||1 : 3: 6||10 MPa||1450 psi|
|M15||1: 2: 4||15 MPa||2175 psi|
|M20||1: 1.5 : 3||20 MPa||2900 psi|
|Standard Grade of Concrete|
|M25||1: 1 : 2||25 MPa||3625 psi|
|M30||Design Mix||30 MPa||4350 psi|
|M35||Design Mix||35 MPa||5075 psi|
|M40||Design Mix||40 MPa||5800 psi|
|M45||Design Mix||45 MPa||6525 psi|
|High Strength Grade of Concrete|
|M50||Design Mix||50 MPa||7250 psi|
|M55||Design Mix||55 MPa||7975 psi|
|M60||Design Mix||60 MPa||8700 psi|
|M65||Design Mix||65 MPa||9425 psi|
|M70||Design Mix||70 MPa||10150 psi|
The Selection of the Grade of Concrete Depends on the Situation and Uses
|Concrete Grade (N/mm2)||Ratio Cement, Sand, and Aggregates||Usage|
|20||1:1.5:3||Normal Construction Concrete|
|30||Concrete Mix Design||Heavy Reinforced concrete/pre-cast|
|35||Concrete Mix Design||Pre-stressed/pre-cast concrete|
|40||Concrete Mix Design||Very heavy reinforced concrete/pre-cast/prestressed|
|45||Concrete Mix Design||Very heavy reinforced concrete/pre-cast/prestressed|
Watch Video: What is Grade of Concrete and Different Types used in Construction
c16/20 concrete meaning
In C16/20 concrete grade, C refers to concrete strength, 16 number indicates its characteristics of compressive strength (fck) on cylinder test that is 16MPa and numerical figure 20 represents its characteristics of compressive strength (fck) on cube test that is 20MPa.
Grade of Concrete
Grades of concrete are defined by the concrete mix proportion and the minimum strength of concrete at end of 28 days curing period. The Concrete Grade is can be known by calculating the compressive strength of concrete in Mpa, where M stands for mix and the MPa denotes the overall strength
Concrete Grade is defined by the concrete mix proportion and the minimum strength of concrete at end of 28 days curing period. The Concrete Grade is can be known by calculating the compressive strength of concrete in Mpa, where M stands for mix and the MPa denotes the overall strength
concrete grade c25/30 meaning
In C25/30 concrete grade, C refers to concrete strength, 25 number indicates its characteristics of compressive strength (fck) on cylinder test that is 25MPa, and numerical figure 20 represents its characteristics of compressive strength (fck) on cube test that is 30MPa.
concrete grade 30
Concrete grade 30 does not have a standard concrete mix ratio. To make M 30 grade of concrete, we have to prepare a mix design for it as per IS Code. In M 30, M is for Mix, and 30 is the design compressive strength of concrete,
You May Also Like
- What is RCC – Reinforced Cement Concrete
- Concrete Mix Ratio | Concrete Ratio | Concrete Proportions | Concrete Mix Ratio Table | Concrete Grade Ratio | Concrete Mix Design Ratio
- How Many Bags of Concrete Do I Need For 10×10 Slab
- How Many Bags Of Concrete In A Yard | How Many Bags of Concrete Do I Need
- What Is Plain Cement Concrete (PCC) – Materials, Uses & Grades
- Concrete Mix Design | Concrete Mix Design Calculations pdf | Concrete Mix Design Excel Sheet | IS 10262 Code 2019 pdf Download | Mix Design Code
- Site Mix Concrete Vs Ready Mix Concrete – Which is Better
- Mix Design of Concrete For M20, M25, and M30 With Procedure