Steel Bar Weight Calculation

For Flat Bar

1-meter length of Mild Steel bar of size 40 mm width and 20 mm breadth

Weight  = Volume X Density

= width (mm) X Thickness (mm)  X 7.85 Kg/mm³

= (40 X 20) X 0.00785 (converted the 7850 kg/m³ to 0.00785 g/mm³)

= 6.28 Kgs/ metre

For Circular Rebars

                                                

Formula for Unit weight of steel = D²/162.28  Kg/m

Let’s take an example,

If we want to calculate the unit weight of 8mm steel rod of 2-metre height,

Weight of steel = 8²/162.28

= 0.3944 kg/m * 2m

= 0.79 kg

What is D²/162.2 in this calculation?

Here is the derivation of that D²/162.2,

Weight of steel bar per meter = Area of the steel x Density of steel x Bar length

= (3.14 x D² /4)  x  7850 kg/m³  x 1m (refer these posts basic formulas & unit weight of materials)

= (D² x 6162.25)/(1000 x 1000)

= D² X (0.006162)

= D² X 1/(0.006162)^-1

= D²/162.28