Bar Bending Shape Codes – Formulas

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