Mostly for small house construction, the reinforcement will be calculated just based on the thumb rule. The excess procured steel will be used for other works.

But for a large-scale project, the tedious BBS schedule will be prepared to avoid the unnecessary wastages.

Bar bending shape codes are the cutting length formula used to avoid unnecessary cut wastes on reinforcement.

Advantages of using BBS codes in BBS Schedule

  • To minimise the wastage
  • To cut the steel bar easily based on the shape code
  • To procure the accurate quantity of material

Standard Bar Bending Shape Codes

Bar Bending Shape Cutting Length of Bar
L = A
L = A+B-0.5r-d
L = A+B+C-r-2d
L = A+B+C-r-2d
L = 2(A+B)-2.5r-5d+Hook
L = A-3.2D+2Hook
L = A+B+2Hook
L = A+B+C+D-2r+Hook
L = A+B+C
L = Cπ(d-A) A-Spacing C-Nos of turns
L = A
L = A+C
L = A+B+C
L = A+B+C+D+E
L = A+C+D
L = A+B+C+D-0.5r-d
L = A+B+C+D+E
L = A+B+C+D-1.5r
L = A+B+2C-2.5r
L = 2A+2B-2.5r+2Hook
L = A

Notes:-

  • The end or side covers for steel bar may be taken as 4cm to 5cm
  • The bottom & top covers should be in the range of 1cm to 2cm.
  • The covers for beam shall be taken as 2.5cm to 5cm.
  • The length of one hook is 9 dia of the bar but not less than 75mm.

Minimum Scheduling Radius, Diameter, and Bend Allowance

Nominal Size of Bar (d) Minimum Radius for Scheduling (r) Minimum Diameter of Bending General (min 5d straight), including links where bend >150⁰ Links Bend <150⁰
6mm 12 24 110 110
8mm 16 32 115 115
10mm 20 40 120 130
12mm 24 48 125 160
16mm 32 64 130 210
20mm 70 140 190 290
25mm 87 175 240 365
32mm 112 224 305 465
40mm 140 280 380 580
50mm 175 350 475 725

Author

Bala is a Civil Engineer who has more than 9+ Years of experience in planning & costing in Infrastructure. He is the author, editor of Civil Planets.

Write A Comment