How to calculate weight of steel bars? Formula for calculating weight of steel in meter & feet

 

         How to calculate weight of steel bars?

The weight of steel bars can be easily calculated by the formula in both the units’ kg/m and also in kg/ft.

Quantity estimation of the materials used on the site like sand, cement, aggregate and steel bars are very important to find out in order to find out the prior budget of the project.

 

Steel Bars of various Dia Used In Construction Industry:

 

8 mm, 10 mm, 12 mm, 16 mm, 20 mm, 25 mm, 28 mm, 32 mm, 36 mm and 40 mm dia steel are generally found in market for general use.

For some special projects the dia which is not found in the market, the companies has to give special order to the steel manufacturing companies. Projects like the Sea harbor, heavy bridges, airports and underground metro projects are some of the examples of such projects.

Calculation of Weight of steel bar for 1 metre Length

 

Weight of steel bar = Volume of steel Bar x Density of steel

We know the Density of Steel = 7850kg/m3

So, Weight of steel rod = (Cross sectional area of steel rod x Length) x 7850kg/m3

                               = π/4 x d² × 1000 × 7850 kg/m3   (length of rod = 1000 mm)

                            = (3.14 x (D² /4) x L) x 7850kg/m3

                             = (D² x 6162.25L)/1000000

                             = D² L x 0.006162

     = D² L / 162.28

Hence,

Weight of Steel Bar  = [ D² L / 162] in Kg/m

Weight of Steel Bar = [ D² L / 533] in Kg/ft

 

 

Let us take an example of Steel Bar of Dia 16.

As we know the formula is:  [ D² L / 162] for Kg/m & [ D² L / 533] for Kg/ft

Hence, the weight of steel Bar of 16 dia

= (D²*L/162) kg/m   &      (D²*L/533) kg/ft

= (256*1/162) kg/m          &     (256*1/533) kg/ft

= 1.58 kg/m     &      0.48 kg/ft

 

Weight of Steel Bars of different Dia :

Dia of Steel	Wt./meter	Wt./feet
8	0.395	0.12
10	0.617	0.18
12	0.888	0.27
16	1.58	0.48
20	2.46	0.75
25	3.85	1.17