The allowable bending stress in a member subjected to bending is
calculated based on the following formula.
For an I-beam or channel with equal flanges bent about the axis of maximum
strength (z-z axis), the maximum bending compressive stress on the extreme fibre calculated
on the effective section shall not exceed the values of maximum permissible bending
compressive stress. The maximum permissible bending compressive stress shall be obtained by
the following formula: (Clause: 6.2.2)