How to calculate Quantity of Cement ,Sand And Aggregate in slab

                        How to calculate Quantity of Cement ,Sand And Aggregate in slab

Example 

Let suppose we have a two way slab having a length of 20 feet and same as width 20 feet and use M15 grade concrete , calculate the quantity of cement sand aggregate that are used in slab and thickness of slab is 6 inch ?

Given Data

Length = 20 feet

Width = 20 feet

Thickness = 7 inches

Solution 

First, we calculate the volume of slab and then this volume is converted into a wet condition to dry condition and then find out material required for slab.

Total volume of slab = L ⨯ W ⨯H

                                 = 20 ⨯ 20 ⨯ 0.583 = 233.2 cft

Convert wet volume into dry volume

Dry volume = wet volume ⨯ 1.54 (wastage of sand Bulking all include)

                    = 233.2 ⨯ 1.54 = 359.13 cft

Ratio of concrete (1:2:4 = 7)

Volume of cement

vol of cement =  1/7 ⨯ 359.13

                       = 51.30 cft

Convert this volume into cement bag. we get 1.25 cuf  in one cement bag

= 51.30 / 1.25

=41.04

Volume of sand 

Vol. of sand = ratio of sand / total ratio ⨯ volume

                   = 2 / 7 ⨯ 51.30

                   = 14.65 cft

Volume of Aggregate 

Vol. of aggregate = ratio of agg / total ratio ⨯ volume

                            = 4 / 7 ⨯ 51.30

                            = 29.31 cft.

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