types of columns

Column:A column is defined as a compression member, the effective length of which exceeds three times the lateral dimension less. Compression members whose lengths not exceeding three times the smaller lateral dimension, may be made of mass concrete.

 Types of reinforcement

Longitudinal  reinforcement

Minimum area of the cross section of the longitudinal bars must be at least 0.8% of the gross section area of the column.

  The maximum area of the cross section of the longitudinal bars must not exceed 6% of the gross area of the column cross section.The bars should not be less than 12 mm in diameter.Minimum number of longitudinal bars shall be four in the rectangular column and 6 in the circular column.Longitudinal bars spacing measured along the periphery of a column should not exceed 300 mm.

Transverse reinforcement

It is perhaps in the form of lateral loops or spirals. The diameter of the lateral links should not be less than 1 / quarter the diameter of the largest longitudinal bar and in no case less than 6 mm.The tone of the lateral links should not exceed,Lateral dimension less,16 times the diameter of the longitudinal bars (small),300mm

Helical reinforcement

The diameter of the helical rods should not be less than one / fourth of the diameter of the largest longitudinal and not less than 6 mm.

The pitch should not exceed (if helical reinforcement is allowed);

      75mm,One / sixth of the core diameter of the column,Pitch should not be less than,25mm,3 times the diameter of the helical rod

Should not exceed pitch (helical reinforcement if not allowed)