# Bar Bending Shape Codes

Shape codes are the building stones of a perfect bar bending schedule.

When calculating the reinforcement detailing for different members for a building, taking account of small bent ups and other angle detailing will make the difference of effective and economic BBS.

This is will effectively minimise the cost and wastage of reinforcement.

We have already covered how to calculate a cutting length of bent up bars? which is also useful for this explanation.

Let’s get started,

You may be noticed in beams & slabs there are number different bent ups, cuttings, and development lengths. Each and every bend and angle provided in the member is the result of design calculation. So we should precise about implementing those in practice.

However for small projects, we don’t calculate these details, we just add a few more inches and calculate the Bar Bending Schedule.

In the upcoming posts, we are going to discuss Bar Bending Schedule in more detail. So be familiar with the below shape codes.

Bar Bending ShapeTotal length of bar (L) L = A A+(B)-0.5r-d A+(B)-0.43R–1.2d A+0.57B+(C)-1.6d A+(B)-4d A+(B) A+B+(C)-r–2d A+B+C+(D)-1.5r–3d A+B+(C)–r–2d A+B+(C) A+B+(C) A+B+(C) A+B+(C)-0.5r-d A+B+(C)-0.5r-d A+B+(C)-r-2d A+B+C+(D)-1.5r-3d A+B+C+(D)-1.5r-3d 2A+ 1.7B+2(C)-4d A+B+C+(D)-0.5r-d A+B+C+(D)-0.5r-d A+B+C+(D)-r-2d A+B+C+D+(E)-2r-4d A+B+C+D+(E)-2r-4d A+2B+C+(D) 2A+B+2C+1.5r-3d 2(A+B+C)-2.5r-5d A+B+C+(D)+2(E)-2.5r-5d 2A+3B+2(C)-3r-6d A+2B+C+D+E+F-3r-6d A π (A – d)+B Cπ(A-s) A+2B+C+(D)-2r-4d

### Minimum scheduling radius, former diameters, and bend allowances

Nominal size of bar, d, mm Minimum radius for scheduling, r 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

Happy Learning 🙂