the youtuber SL Khan has made a lovely presentation of the details for designing a square shaped column by reinforced concrete. The basis used here are the ACI codes: the first and foremost thing before designing the column is making a right percentage of longitudinal steel. It should not be less than 1% not more than 8%. The perfect shape can be made (rectangular or circular ties) by using four longitudinal bars. See more and learn something new from the video bellow.

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