CALCULATION OF MATERIALS FOR DIFFERENT MIX RATIO:

Quantity estimation of materials is essentially required in any construction works and quantity of materials depend on the mix proportions of the concrete. In our previous article, we have already discussed how to calculate bricks in a wall.  Today we will discuss how to calculate quantities of materials for different mix ratio of concrete. (Dry mix method)

We will calculate quantities of materials for 1 m3 concrete (By volume).

Let us assume the mix proportion is 1 : 2: 4 (cement:sand:stone =a:b:c)

Volume of wet concrete = 1 m3

Volume of dry concrete = 1 × 1.54 = 1.54 m3

What Is 1.54 Given Below:

CALCULATION FOR CEMENT:

Formula, Cement = (Volume of dry concrete/a+b+c) × a

= (1.54/a+b+c) × a = [(1.54/1+2+4)] × 1 = 0.22 cum

Now density of cement = 1440 kg/cum

∴ Volume of cement = 0.22 ×  1440 =316.8 kg.

As we know, 1 bag of cement contains 50 kg of cement .

∴ Cement bags required = 316.8/50 = 6.33 bags.

CALCULATION FOR SAND:

Formula,  Sand = (Volume of dry concrete/a+b+c) × b

= (1.54/a+b+c) × b = (1.54/1+2+4) × 2 = 0.44 cum.

CALCULATION FOR STONE CHIPS:

Formula, Stone Chips = (Volume of dry concrete/a+b+c) × c

= (1.54/a+b+c) ×c  = (1.54/1+2+4) × 4 = 0.88 cum.

CALCULATION FOR WATER CONTENT:

Let us assume the water/cement ratio of the concrete is 0.45.

w/c = 0.45

Required water for 1 bag cement = 0.45 × 0.0353 = 0.0159 cum.

Where volume of 50 kg cement = 0.0353 cum

1 m3 water = 1000 Litre

Required water for 1 bag cement=0.0159 × 1000 = 15.9 Litre.

∴ Required water for 6.33 bags cement = 6.33 × 15.9 = 101 Litre.

SUMMARY:

Cement = 6.33 bags.

Sand = 0.44 cum

Stone chips = 0.88 cum

Water = 101 litre.

Note: Yield of concrete is considered as 67% &

Wastages of materials = 2%

You can use the same formula for different mix proportions such as 1:1.5:3 etc.

Here, we have used cubic meter unit but you can also calculate in cubic feet unit.