BBS OF COLUMN

BAR BENDING SCHEDULE OF COLUMN

  • The height of the column is 3 meter and having a cross sectional dimensions are 450 x 600 mm and having a 40 mm of clear cover. There are 12 bars used of 16 mm as a main vertical bars. The diameter of stirrups are used at 100 mm and 150 mm c/c at L/4. So calculate the cutting length of bars and stirrups?
Given data:-
Height - 3 meter
Cross sectional dimensions - 450x600 mm
Clear cover - 40 mm
No.of vertical bars - 12 nos
Dia. Of vertical - 16 mm
Dia. Of stirrups - 10 mm
C/C distance of stirrups - 100 & 150 mm

  1. Vertical bar calculation
Length of 1 bar - H + Ld
Where, H - Height of column
               LD - development length

Length of 1 bar = 3000 mm + 47d
                             = 3000 + 47*16
                             = 3000 + 752
                             = 3752 mm

We have total 12 bars so total length of all bars are,
             3.752 m X 12 nos = 45.024 m

   2. Stirrup calculation
   Cross sectional dimensions - 450 X 600 mm
   Let assume the 450 mm as A side and
                               600 mm as B side of column

Calculation of A = 450 - 2 X clear cover
                              = 450 - 2 X 40 mm
                              = 450 - 80 mm
                              = 370 mm

Calculation of B = 600 - 2 X clear cover
                              = 600 - 2 X 40 mm
                              = 600 - 80 mm
                              = 520 mm

No of stirrups = 3000 / 4 = 750 mm
There are two zones of 100 mm 
Spacing and two zones of 150 mm.

At end zones, 
                         1500 / 100 = 15 Rings
At mid zones, 
                          1500 / 150 = 10 Rings
Total no. Of stirrups = 15 + 10 = 25 Rings

Cutting length of one stirrup

Formula- (2xA) + (2xB) + hook - bend.
Where, 
               Hook = 10d
               Bend = 5x 2d (because we have 5 bend)
               d = Dia of bar
          = (2x370) + (2x520) + (10x10) - (2x5x10)
          = 740 + 1040 + 100 -100
          = 1780 mm
We have total 25 stirrups so total length is, 
           = 25x 1.78 m 
           = 44.5 m long 10 mm bar.


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