Calculate the Cement, Sand and Stone quantities for M20(1:1½:3) Grade of Concrete

The mix ratio for M20 grade concrete is typically 1:1.5:3. This means that for each 1 box of cement, you have to add 1.5 boxes of fine aggregate and 3 boxes of coarse aggregate.

1 box of cement : 1.5 boxes of fine aggregate : 3 boxes of coarse aggregate

Let us calculate the quantities of Cement, Fine aggregate, Coarse aggregate and Water quantity to get 1 m³ of Concrete.

Concrete Grade M20 Ratio = 1:1.5:3

Total number of boxes = 1+1.5+3 = 5.5 boxes.

Total volume needs to be calculated = 1 m³

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Volume of Cement:

Volume of cement/Total Volume = 1/5.5

Volume of cement = 1/5.5 * Total Volume

= 1/5.5 * 1

= 0.182 m³

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Volume of Fine Aggregate:

Volume of Fine Aggregate/Total Volume = 1.5/5.5

Volume of Fine Aggregate = 1.5/5.5 * Total Volume

= 1.5/5.5 * 1

= 0.273 m³

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Volume of Coarse Aggregate:

Volume of Coarse Aggregate/Total Volume = 3/5.5

Volume of Coarse Aggregate = 3/5.5 * Total Volume

= 3/5.5 * 1

= 0.545 m³

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Volume of Water:

Water-Cement Ratio = 0.45

Volume of Water/Volume of Cement = 0.45

Volume of Water = 0.45 * Volume of cement

= 0.45 * 0.182

= 0.0819 m³

= 0.0819 * 1000 lit (1 m³ = 1000 liters)

= 81.90 liters

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For M20 Grade of Concrete, the quantities in m³ are :

Cement : Fine Aggregate : Coarse Aggregate = 0.182 m³ : 0.273 m³ : 0.545 m³

For M20 Grade of Concrete, the quantities in kgs are :

To calculate the quantity in kgs, we have to find the density of Materials,

As per NBC;

The density of cement = 1440 kgs

The density of River sand = 1840 kgs

The density of Broken Ballast Stone = 1600 kgs

Cement : River Sand : Ballast stone = 0.182 * 1440 kgs : 0.273 * 1840 kgs : 0.545 * 1600 kgs

Cement : River Sand : Ballast stone = 262.08 kgs : 502.32 kgs : 872 kgs

Cement : River Sand : Ballast stone = 262 kgs : 502 kgs : 872 kgs

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Summary:

• Mix Ratio: 1:1.5:3 (Cement: Sand: Coarse Aggregate)
• Total Volume: 1 m³

1. Cement:

• Volume = 0.182 m³
• Density = 1440 kg/m³ (as per NBC)
• Quantity = (Volume * Density) ≈ 262 kg (or 5.3 bags)

2. Sand (River Sand, Dry):

• Volume = 0.273 m³
• Density = 1840 kg/m³ (as per NBC)
• Quantity ≈ 502 kg

3. Coarse Aggregate (Ballast Stone, Dry):

• Volume = 0.545 m³
• Density = 1600 kg/m³ (as per NBC)
• Quantity ≈ 872 kg

4. Water:

• Water-Cement Ratio = 0.45
• Volume of Water = 0.45 * 0.182
• Quantity = (Volume of Water * 1000) ≈ 81.90 liters

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