Basically, the reinforcement is provided in concrete to develops the tensile strength of concrete because of the concrete having low tensile strength.

An accurate bar bending schedule can able to prepare based on the bar bending schedule formulas. In Fact, the bar bending schedule formulas are called Bar bending shape codes.

Each bar shape has an individual formula to calculate the length.

You may aware there are different kinds of bar shapes are using in reinforcement. The reinforcement design depends on the load calculation.

## Bar bending shape codes

Mostly for small-scale projects, the reinforcement calculated just based on the thumb rule but that was wrong. At the same time for large-scale project the BBS schedule prepared by the bar bending shape codes to avoid the unnecessary wastages.

Moreover, if we prepared the bar bending schedule along with the bar bending shape codes, it could be easy to cut the steel bar for the reinforcement as per the design.

Advantages of using BBS codes in BBS Schedule

- Minimise the wastage
- To cut the steel bar easily based on the shape code
- Accurate material procurement
- Avoiding unnecessary confusion

## Standard BBS Codes

### Notes:-

- The end or side covers for steel bar may be taken as 4cm to 5cm and 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 >150 Deg | Links Bend < 150 Deg |

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 |