How to estimate bar bending schedule of Octagonal Footing

Get some useful tips for estimating bar bending schedule of octagonal footing. The process is similar to compute BBS toward a square or rectangular footing. Here, only the shape will vary. Octagonal footing is mostly recommended in Petrochem industry.

The reinforced bars are arranged as same as square footings but their cutting length differs as they touch the corners.

BBS of an octagonal footing will contain length of the element, cross section, no. of bars, type of bars, spacing between the bars, lap length (horizontal/vertical), development length, covers for footing/column/beam/slab.

Process for computing the cutting length of the bars :-.

From total length subtract covers on both side and add development length i.e.
(Total Length ? Covers on both side) + Development Length

To do this, the following formula will be used :-
W = N x CL x U

Here, W stands for weight of reinforcement

N stands for no. of bars
CL stands for cutting length
U stands for unit weight

Unit weight can be obtained from charts or by applying the following formula :-
U = D x D/162

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