The bar should not be under 12 mm.

The nominal cover shall any case should not be under 40 mm.

Lowest distance between individual bars should be as follow :-

  • the diameter of greater bar
  • 5 mm more nominal maximum size of coarse aggregate

Spacing of longitudinal bars should not be in excess of 300 mm from the edge of the column.

For rectangular column, the reinforcement should be allocated evenly on four sides.

The numbers of bars in column differs from 10, 12, 14, 16 of changeable diameter.

They produce main bars with various diameter ranging from 16mm, 20mm, 25 mm.

For circular column, there should be 6 nos. 20 mm dia. bar and 6 nos. 16mm dia bar.

The effective length should be 48 times the diameter of bar.