# Wiki source code of Flange reinforcement

1 If the concrete section has flanges and an excentric load is placed on that flange, hanging reinforcement needs to be calculated in order to avoid the flange shearing off.
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3 The calculation model is defined as a strut-n-tie model according to the picture below.
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5 [[image:flange 1.jpg||height="300" width="254"]][[image:flange 2.jpg||height="300" width="407"]][[image:flange 3.jpg||height="300" width="513"]]
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7 The calculation is carried out as an iterative process according to the following schema:
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9 The goal is to find F,,s,, which is the force that should be reinforced for.
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11 Step 1: Make an educated guess for 'x'.
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13 Step 2: Calculate z = h - t,,1,, - t,,2,, - x/2.
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15 Step 3: Calculate F,,s,, = F,,c,, = (F,,v,, * a) / z
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17 Step 4: Calculate new x = F,,c,, / f,,cc,,.
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19 Step 5: Go to Step 2 while x has not significantly changed since last iteration, otherwise we have found F,,s,,.
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21 The distribution of the flange reinforcement is determined according to the right side pictures above.
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23 B = 4 * h + b
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25 For point loads the load width (b) is 0, for distributed loads b is equal to the distribution length.
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27 See [[Viewing the design results>>doc:PRE-Stress.PRE-Stress User Manual.Viewing the design results.WebHome]] for the how the flange reinforcement results are presented.