Assume clear cover of 40mm
1) Length of top straight bars
L= Length of beam – 2×cover + (2×9×d)
=5000 - (2×40) + (2×9×12)
=5135m
2) Length of bottom straight bars
L= Length of beam – 2×cover + (2×9×d)
=5000 - (2×40) + (2×9×16)
=55208m
3) Length of bent up bars
L= Length of beam – 2×cover + (2×9×d) + [No.of bent up×0.42D]
L= 5000 – 2×40 + (2×9×16) +[2×0.42×420]
=5555.76m
4) Length of Stirrups
L= {[2×(depth – 2×cover)]+ [2×(depth – 2×cover)]}×24d
L= {[2×(500 – 2×40)]+ [2×(230 – 2×40)]}×24×8
L=1332m
No. of Stirrups $=\frac{L-2*cover}{spacing}+1 \\
=\frac{1332-2*40}{150}+1 \\
=9.34m =10 no.s (say)$
No |
Description of bar |
Length of each (m) |
No |
Total length (m) |
Wt Kg/m (ф²/162) |
Wt kg |
1 |
Straight top bar (12dia) |
5.136 |
2 |
10.27 |
0.89 |
9.14 |
2 |
Straight bottom bar (16dia) |
5.208 |
2 |
10.416 |
1.6 |
16.66 |
3 |
Bent up bar (16dia) |
5.555 |
2 |
11.11 |
1.6 |
17.76 |
4 |
Stirrups (8 dia) |
1.332 |
10 |
13.32 |
0.4 |
5.328 |
Total weight = 48.88kgs = 49kgs (Say)
To find out quantities
Assume M20 grade (1:1.5:3)
1) Concrete Quantity = 50.230.5=0.575m³
2) Consumptive steel $=\frac{\text{Total weight}}{\text{concrete quantity}}=\frac{48.88}{0.575} \\
=85.02 kg/m³$