We shall easily estimate the concrete quantity for a slab, beam or column by multiplication of its measurement Length, Breadth & Depth.

But we may struggle to calculate the ingredients of concrete because the estimation of material should have the accuracy to avoid the cost implement.

So let us discuss the concrete material calculation with an example.

#### The dimension of the Slab

Length – 5m Breadth – 2m Depth – 0.1m Grade of concrete – M15

## How to calculate cement, sand and coarse aggregate for concrete?

M15 Mix Ratio – 1 : 2 : 4

The mix ratio denotes the following

1 – Cement

2 – Sand (Fine aggregate – 2 Times of Cement Quantity)

4 – Blue metal (Coarse aggregate – 4 Times of Cement Quantity)

The volume of concrete – (L x B x D) = 5 x 2 x 0.1 = 1 Cum

Volume of Concrete = 1 Cum

We find out the volume of concrete in wet condition 1m^{3 }(After the consolidation of Cement+sand+water). So in dry conditions, we have to add 30 to 35% sand bulkage and add 20% for wastage.

Bulkage of Sand – 35% Wastage – 20% ( So 1+0.2+0.5 = 1.55 it may vary 1.54 to 1.57). Mostly for estimating 1.54 is taken as constant.

Sum all the proportion of the Mix ratio = 1+2+4 = 7

Total concrete part = 7

Material calculation formula for concrete

**Volume of Cement** – (Cement part x 1.54)/7

– (1 x 1.54)/7 = 0.22 Cum

– (0.22 x 1440)/50 = 6.336 Bags

Unit weight of cement – 1440 Kg/Cum Weight of one cement bag – 50 Kg

**Volume of Sand** – (Sand part x 1.54)/7

– (2 x 1.54)/7 = 0.44 Cum

**Volume of Coarse aggregate **– (Coarse aggregaet part x 1.54)/7

– 4 x 1.54/7 = 0.88 Cum

Once you find the quantity of cement you can directly calculate the Sand and metal volume through cement quantity.

Cement Quantity – 0.22 Cum (6.336 in terms of bag)

Sand – 0.22 x 2 – 0.44 Cum

Coarse Aggregate – 0.22 x 4 – 0.88 Cum.

Don’t forget to calculate the quantity of water for mixing. How to calculate the water-cement ratio?

As per IS code we take 0.40 as Water/ Cement (W/C) Ratio.

So required water – 0.4 x 50 x 6.336 = 126.72 Liters for 1 Cum

So the required material for 1cum concrete

Cement – 6.336 bags Sand – 0.44 Cum Coarse aggregate – 0.88 Cum Water – 126.72 Liters

### Here we list out the Material requirement for Different Grade of Concrete

Grade | Ratio | Cement in Bags | Sand in Cum | Coarse Aggregates in Cum |
---|---|---|---|---|

M5 | 1:5:10 | 2.77 | 0.48 | 0.96 |

M7.5 | 1:4:8 | 3.41 | .047 | 0.95 |

M10 | 1:3:6 | 4.44 | 0.46 | 0.92 |

M15 | 1:2:4 | 6.34 | 0.44 | 0.88 |

M20 | 1:1.5:3 | 8.06 | 0.42 | 0.84 |

M25 | 1:1:2 | 11.09 | 0.39 | 0.77 |

You may like to know How to calculate cement sand quantity for plastering

## Mo shay

Sir, i cant understand the difference between ACI code and IS code of water cement ratio. Pls explain me

## Mo shay

Sir, do u have a conatruction materials calculator software in google playstore, then if u have it software pls give a link of software. Thank u

## Civilplanets

We are working on that!.. update will soon

## Pavan

M30 concrete using only 380kgs with admixture is it possible

## Civilplanets

Yes you can!.

The mix proportion of M30 (Design Mix) is based on the weight of the material. As per the design some percentage of admixture might be mixed with the concrete.

## Raj

Thank you