BBS FOR COLUMN

BAR BENDING SCHEDULE OF THE COLUMN IN DETAILS

The above figures shows the different dimensions of the column and its cross section.

In column 4 bars having 25mm dia and 2 bars having 20mm dia, then total 6 bars are provided in the above column.

There for the main aim is to find total length and weight of the steel bars in the column.

Length of the 20mm dia bar:

We are going to find out the length from bottom of the bar to top of the bar

Take 300mm as anker length at bootom of the column is given in structural diagram sheet if not given take 16×d (where “d” is dia of the bar).

Footing depth = 500mm

Clear cover of the footing = 50mm

Dia of longitudinal and lateral bars of footing = 25mm

Plinth level = 600mm

Plinth beam = 200mm

Floor height = 3000mm

Slab thickness = 175mm

Take anker length at slab = 50×d

And take 2×d for one bent for 90˚

Length of the bar= Anker length at bottom+(height of the footing – clear cover -2×dia of bars) + plinth level + plinth beam height + floor height + slab thickness + floor height + ( anker length at the column end ) – number of bends

     

=300+(500-50-2×25)+600+200+3000+175+3000+(50×20)-(2×2×20)

= 8595mm

= 8.595m

For 4 bars total length = 34.38m

Heare in case bar length is greaterthan 12m we add lap joint lenght also

(lap joint length is 50×d ; where d is dia of the bar)

Now finding length of the 13mm dia bar:

Length of the bar= Anker length at bottom+(height of the footing – clear cover -2×dia of bars) + plinth level + plinth beam height + floor height + slab thickness + floor height + ( anker length at the column end ) – number of bends

=300+(500-50-2×25)+600+200+3000+175+3000+(50×16)-(2×2×16)

=8461mm

=8.461m

For 2 bars total length = 2×8.461m

=16.922m

Heare also in case bar length is greaterthan 12m we add lap joint lenght also

(lap joint lenght is 50×d ; where d is dia of the bar)

 Cutting length

Cutting length for main bars:

Cutting length is same as length of the bars becouse there is no any lapp joint.

Cutting length for stirrups:

Stirrup length = ( width of the column – two sides clear cover ) + (bredth of the column – two sides of the clear cover ) + (no of hooks × 10d) - (no of bends × 2d)

= (600-2×40) + (300-40)+(2×10×8)-(5×2×8)

= 860mm

= 0.860m

At  A:

Lenght = (500-50-25-25)+600+200+500

1700mm

Spacing of stirrup = 100mm c-c

No of stirrups =  + 1

 + 1

=17 + 1

=18 nos

At  B:

Length = 2000mm

Spacing of stirrups = 150mm c-c

No of stirrups =  - 1

 - 1

= 13.33 – 1

=12 nos

At  C:

Length = 500+175+50

=1175mm

Spacing of the stirrups = 100mm

No of stirrups =  + 1

 + 1

= 11.75 + 1

= 13 nos

At  D:

Length = 500+150-30

=680mm

Spacing = 100mm

No of stirrups =  + 1

=  + 1

=6.8+1

= 8 nos

Total nos = A+B+C+D

=18+12+13+8

=51 nos

S.NO	Description	Length	No	Total length	Weight ( ×l )
1	25mm dia bars	8.461m	4	34.38m	132.62kg
2	16mm dia bars	8.461m	2	16.922m	26.74kg
3	8mm dia stirrups	0.860m	51	43.86m	17.32kg