a) the total cross-sectional area of the longitudinal steel reinforcement shall not be less than 0,4 per centum of the gross cross-sectional area of the column;

b) there shall be at least one bar for each salient angle in the cross-section of the column;

c) lateral ties shall be provided of a total volume of not less than 0,4 per centum of the gross volume of the column, and shall have a diameter of not less than 6 millimetres;

d) the lateral ties shall have their ends anchored , welded together or lapped through a distance equal to 50 times the diameter of the longitudinal bars or the least lateral dimension of the column, whichever is the least.

e) The spacing of the lateral ties shall not exceed 400 millimetres or 16 times the diametre of the longitudinal bars or the least lateral dimension of the column, whichever is the least.