[Solved] The grade of concrete M 20 means that compressive strength o (2024)

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[Solved] The grade of concrete M 20 means that compressive strength o? ›

The number that follows the "M" represents the compressive strength of the concrete mixture in megapascals (MPa) after 28 days. For example: M15 concrete has a compressive strength of 15 MPa after 28 days. M20 concrete has a compressive strength of 20 MPa after 28 days.

Megapascal or MPa is the unit of measure used to denote the grade of cement. The grade is categorised into groups such as ordinary, standard, and high strength. A grade of 20 MPa is referred to as M20 grade and comes under the ordinary grade group.

C20 concrete strength in PSI is 2900, or 20 newtons after 28 days, which makes it best suited to domestic applications where only a lightweight mix is required.

∴ In the designation of a concrete mix, the letter 'M' and the number stands for Mix and characteristic compressive strength of 150 mm cube at 28 days. ∴ The M 15 grade of concrete means the concrete mix which attains 28 day strength (characteristics) as 15 MPa or 15 N/mm².

It is considered as the minimum nominal mix of concrete for Reinforced Cement Concrete (RCC) works. The M20 grade indicates the strength of the concrete, which is 20 megapascals (MPa) or 20 Newton per square millimetre (N/mm²) after 28 days of curing.

Compressive strength can be defined as the capacity of concrete to withstand loads before failure. Of the many tests applied to the concrete, the compressive strength test is the most important, as it gives an idea about the characteristics of the concrete.

Once these data points have been taken, the compressive strength of concrete can be calculated using this formula: CS = F ÷ A, where CS is the compressive strength, F is the force or load at the point of failure and A is the initial cross-sectional surface area.

M/20 represents a 0.05 Molar solution means there are 0.05 number of moles dissolved per litre of the solution.

Characteristic strength of M20 concrete is 20 MPa.

What is the strength of grade 20 concrete? ›

Strength: 20 Newtons after 28 days.

Concrete at this strength is often applied on domestic floors and foundations where the weight of overall structures on the concrete will be lighter. C20 is ideal for domestic workshop and garage bases as well as driveways and internal floor slabs.

The mix proportion for C20 concrete usually consists of 1 part cement, 2 parts fine aggregate (sand), and 4 parts coarse aggregate (gravel), along with the necessary water content. 🏢 On the other hand, M20 concrete grade represents a higher strength mix with a compressive strength of 20 MPa after 28 days.

For instance, when concrete is classified as C 20/25, it implies that for such concrete 95% of all compressive strength determinations would have a 28 days' compressive strength greater than or equal to 20 N/mm² when the concrete is cast into 150 mm diameter by 300 mm cylinders or greater than or equal to 25 N/mm² when ...

The maximum strength developed by the concrete M20 on 28 days curing is 22.09 MPa, whereas after 15 days, same concrete mix gains 18.17 MPa.

Measuring the compressive strength of materials

The formula to calculate compressive strength is F = P/A, where: F=The compressive strength (MPa) P=Maximum load (or load until failure) to the material (N) A=A cross section of the area of the material resisting the load (mm2)

The mix ratio for M20 concrete is 1:1.5:3. It is the required ratio of cement: sand: aggregate. Therefore, if you are using one unit of cement to make concrete, you need to use 1.5 units of sand and 3 units of aggregate. This mix ratio indicates the proportion of cement to sand to aggregate in volume.

The 7 day strength for any Concrete mix SHOULD NOT BE LESS THAN 65% of the Characteristic Strength. So for M20 Concrete 7 day Strength should be more than 13MPa or 13N/mm2 or 130kg/cm2.

Characteristic strength of M20 concrete is 20 MPa.