Let’s assume a typical case where you need to concrete a floor for that day. 

You have to instruct the labourers to bring the required materials from the stock room for the day or you need to buy materials from the store.

In these two scenarios, you need to know the exact material requirements for the concrete volume, if not either you have to bring/buy more materials interrupting the work or you will do partial work. Where the manpower will be totally wasted and impact your cost estimation.

So today’s post, we are going to know How to calculate Cement bags per Cubic meter Concrete? For Nominal Mix

cement bag into cum

Procedure For Calculating Material Quantity In 1 Cubic Meter Of Concrete

Assume the following case,

  • Nominal Mix Ratio is 1:2:4
  • Void Ratio Compressibility 52%
  • Wastage is 3%
  • Density of Cement – 1440 kg / m3

Void Ratio Compressibility

If you fill the shuttering area with blue metal alone it has lots of voids in it which also need to be filled by the other materials such as sand & cement. Such void gap is known as void ratio compressibility which is 30-32% for coarse aggregate & 20% for sand.

So if we need 1 m3 of concrete in wet condition we have to take consideration of the bulking of sand and void ratio compressibility for both coarse & fine aggregate (32%+20%) = 52%

Adding 3% as wastage it comes as 55%.

Thus every time you need to calculate the volume of concrete you need to add the above percentage with dry volume

Wet Volume of concrete = Dry Volume of concrete + 55% of dry volume of concrete or

Wet Volume of concrete = Dry Volume of concrete x 1.55

So whatever volume we get from the above formula, we need to multiply the value with 1.55%

Calculation

We already discussed the volume formula from Concrete Volume Calculation which is

Concrete Volume Formula

Required Cement Quantity for 1 m3 = (Cement Part / Total Parts) x 1.55 = 1/(1+2+4) x 1.55 = 0.221 m3

Unit weight of cement = 1440 kg / m3

Therefore required cement = 1440 x 0.221 m3 = 318.24 Kg or (318.24/50) = 6.37 Bags

Cement Bag Per Cubic Metre Concrete Table – Nominal Mix

Concrete Grade Mix Ratio Cement in Cubic metre Cement in Bags
M5 1:5:10 0.097 2.79
M7.5 1:4:8 0.119 3.43
M10 1:3:6 0.155 4.46
M15 1:2:4 0.221 6.37
M20 1:1.5:3 0.282 8.12

Happy Learning 🙂

Author

Bala is a Planning Engineer & he is the author and editor of Civil Planets.

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