Longitudinal reinforcement in Column

 


Longitudinal reinforcement in Column

  • The cross - sectional area of longitudinal reinforcement , shall be not less than 0.8 present nor more then 6 percent of the gross cross -sectional area of the column .

  • in any column that has large cross-sectional area than that require to support the load the minimum percentage of shall based upon the area of concert requested to resist the direct stress and upon the actual area 

  • The minimum number of longitudinal bars provide in a column shall be four in rectangular column shall be rectangular column in six circular column 

  • The bar shall not be less then 12 mm in diameter 

  • Reinforcement concrete column having helical reinforcement shall have at list six bars of longitudinal reinforcement within the helical reinforcement

  • in a helically reinforcement column the longitudinal bars shall be in contact within the helical reinforcement .and equidistant around its inner circumference 

  • spacing of longitudinal bars measured along the peripheric of the shall not exceed 300 mm.

  • in case of pedestals in which the longitudinal reinforcement is not taken in account in strength calculation nominal longitudinal reinforcement not less than 0.15 percentage of the cross sectional area shall be provide.
Note : The used of 6 percent reinforcement may involve practical difficulties in placing and compacting hence lower percentage is recommended . where bars form the column below hived to be lapped withes 

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