Yes, it is mandatory because it says it will be applied in TDY, but the reason is of course to provide sufficient clamping length. When you apply the item, two results will be reflected in your project. 1. Due to the condition a+b>=lb, the miter lengths of the reinforcements change. 2. Due to condition a, the size of the remaining column in the beam direction may change. Due to condition 2, columns 25 cm wide usually do not save, depending on the diameter of the reinforcement used and the concrete cover. According to the first condition, the height of the piece of reinforcement bent into the column is determined. It is a common practice for a long time to make the miter height equal to the beam height. According to the a+b>=lb condition, the miter length can be left less depending on the situation, but you can make the miter longer if you want because it has a large equal condition. For this reason, the parameter b depending on the beam height is also included as an option in the program. Good work...
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