Bar Bending Schedule of Beam
Here we calculate the bar bending schedule of beam detailed calculation given below:
The quantity of the beam is very easy and simple.Just you need to know about basics of beam.
Let solve this example to understand better.
Example:
Let us we have a simple supported beam having a cross section 300 x 500 mm and length of the beam is 4m.
The main bars used in this beam is 20 mm and support bar diameter is 16mm.The diameter of stirrup is 12 mm and spacing of stirrup is at an end is 100 mm and 150 mm at the mid support of the beams.
- Calculate the required quantity of steel ?
- Cutting length of stirrups ?
- Calculate the weight of steel ?
Given Data:
Length = 4 m
Height = 500 m
Width = 300 m
Solution:
Main bar (20 mm):
Length = length of beam + development length – bend
Where
Bend 45deg = 1d , 90deg = 2d , 135deg = 3d
Development length is the grip between steel and concrete
Length:
= 4000 + (50d x 2) – (2d x 2)
= 4000 + (50 x 20 x 2) – (2 x 20 x2)
= 4000 + 2000 – 80
= 5920 mm or 5.92 m
For 2 nos
= 5.92 x 2
= 11.84 m
Weight
= d²/162 x length
= 20 x 20/162 x 11.84
= 29.2 kg
Supports bar (16mm)
Length = length of beam + Ld – bend
Where
For 90 dig bend = 2d
= 4000 + (50d x 2) – (2d x 2)
= 4000 + (50 x 16 x 2)
= 4000 + 1600 – 64
= 5536 or 5.536 m
For 2 nos
= 5.536 x 2
= 11.072 m
Weight
= d²/162 x length
= 16 x 16/162 x 11.072
= 16.47 kg
Stirrups:
Length is divided into 2 ways 1st is at support and 2nd is at mid support.
For end supports:(spacing 100 mm)
Length / 3:
= 4000/3
= 1333.3 m
No of stirrups
= Length / spacing + 1
= 1333.3/100 + 1
= 14.33 use 15 Nos
Total no of stirrups for end supports
= 15 x 2
= 30 nos
For mid supports: (spacing 150mm)
Length = 1333.3 m
No of stirrups
= length /spacing + 1
= 133.3/150 + 1
= 7.88 use 8 nos
Cutting Length of stirrups:
Cross section of stirrups is
Width = 300 mm
Height = 500 mm
A is Horizontal length of stirrup
= 300 – (2 x clear cover ) – (2 x half of bar dia)
= 300 – (2 x 30) – (2x 6)
= 228 mm
B is vertical length of stirrup
= 500 – (2 x clear cover ) – (2 x half of bar dia)
= 500 – (2 x 30) – ( 2 x 6)
= 428 mm
Cutting length of one stirrups is
Cutting length
= (2 x A) + (2 x B) + (2 x 10D) – (3d x 2) – (2d x3)
Where
10d is hook and 3d is bend 135 for dig and 2d is bend for 90 dig
In one stirrups 5bend is required
Cutting Length:
= ( 2 x 228) + (2 x 428) + (2 x 10 x 12) – (3 x 12 x 2) – (2 x 12 x 3)
= 456 +856 +240 -72-72
= 1408 mm or 1.408 m
For total 38 stirrups
= 1.408 x 38
= 53.50m
Weight of steel req of stirrups is
= d²/162 x length
= 12²/162 x 53.5.
= 47.55kg
Total weight of steel
= main bars + supports bars + stirrups
= 29.2 + 16.47 + 47.55
= 93.22 kg
Read More
Calculation of Cutting Length of a Diamond Stirrups
Bar Bending Schedule of Column Footing
