Introduction to Bar Bending Schedule [BBS]
Bar bending schedule commonly known as BBS is one of the most important terms in Civil Engineering. Because it plays a vital role in building construction. Like other building materials estimation of steel is also required for constructing a building and here BBS comes with an easy solution. Bar bending schedule provides the reinforcement calculation and some other important details such as bar mark, bar diameter, bar shape, cutting length, number of bars, the weight of the bar, the total weight of steel etc. So that we can order the required amount of steel in advance.
Bar Bending Shape Codes
For small projects, we generally use thumb rules for reinforcement calculation. But for large scale project bar bending schedule is prepared by using bar bending shape codes to avoid unnecessary wastages. It also makes easier to cut the steel bar for the reinforcement as per the design.
Bar Bending Shape Codes As Per BS 8666:2005
Different bar bending shaped codes are listed below.
Where L = Total length of the bar
Minimum Scheduling Radius, Diameter And Bend Allowance:
| Nominal size of the bar, d, mm | Minimum radius for scheduling, r | The minimum diameter of bending former | General (min 5d straight), including links where bend ≥ 150° mm | Links where bend ≤ 150° (min 10d straight) mm |
|---|---|---|---|---|
| 6 | 12 | 24 | 110* | 110* |
| 8 | 16 | 32 | 115* | 115* |
| 10 | 20 | 40 | 120* | 130 |
| 12 | 24 | 48 | 125* | 160 |
| 16 | 32 | 64 | 130 | 210 |
| 20 | 70 | 140 | 190 | 290 |
| 25 | 87 | 175 | 240 | 365 |
| 32 | 112 | 224 | 305 | 465 |
| 40 | 140 | 280 | 380 | 580 |
| 50 | 175 | 350 | 475 | 725 |
6 mm, 8mm and 50 mm are non preferred sizes available to special order.
