Bar bending schedule for footing provides you information on the total quantity of steel rods, length of steel rods required and Cutting length of a steel rod at the site. So let us see how we can do it.
Here you can see below the reinforcement detail of an isolated footing. The total length and width of a column are 2000 millimeters and 1500 millimeters respectively. The height of footing is 300 millimeters
Now let us calculate bar bending schedule for footing step by step.
Diameter of Both bars in X direction and Y direction are 12 mm.
Clear cover of the footing is 50 mm.
C/C center to center spacing of steel rods is 150 mm.
Reinforcement detail for bar bending schedule for footing
Calculation of Bar bending schedule for footing
Step – 1 Calculate the effective length of steel rod in X and Y direction using the formula given below.
Effective length = Total length – both sides covers
Effective length along X direction = 2000 – (2 x 500) = 1900 mm
Effective length along Y direction = 1500 – (2 x 500) = 1400 mm
Step-2 Calculate numbers of bars by using formula given below.
Use Spanning of steel rod as mentioned above.
No. of bars along (X) direction = (1400/150) + 1 = 10 nos.
No. of bars along (Y) direction = (1900/150) + 1 = 14 nos.
Step-3 Calculate Cutting length of Steel Bars using formula below
Cutting length of bar along (X) direction:
(Effective length + bends) – bend deductions[1900 + 2(300 – 50 – 50)] – (2 x 2 x 2) = 2252 mm or 2.25 meter
Cutting length of bar along (Y) direction:
(Effective length + bends) – bend deductions[1400 + 2(300 – 50 – 50)] – (2 x 2 x 2) = 1752 mm or 1.75 meter
Bend deduction is calculated as given below
Deduction of the length of bars due to bending at a different angle:
45 Degree = 1d
90 Degree = 2d
135 Degree = 3d
Where d is the diameter of steel rods.
Step-4 Calculate total length of steel rods
Along (X) direction = No. of bars x Length of one bars = 2.25 x 10 = 22.5 meter
Along (Y) direction = No. of bars x Length of one bars = 1.75 x 14 = 24.5 meter
Step- 5 Calculate the unit weight of steel rod using formula
Step-6 Calculate total weight of steel rod
Total Weight of steel = Unit weight x Total Length of steel rod
Add 5% of wastage of steel to get actual total weight of steel bars.
Summary of Bar bending schedule for footing in Table
Watch video on complete Bar bending schedule
Hence in this way we can calculate bar bending schedule for footing.
I hope this article remains helpful for you.
Happy Learning – Civil Concept
Civil Engineer – Ranjeet Sahani