Determine the safe compressive load the column can carry without buckling using Euler’s formula and Rankine’s formula.

Question

A hollow cast iron column of 300 mm external dia and 220 mm internal dia is used as a column 4 m long with both ends hinged. Determine the safe compressive load the column can carry without buckling using Euler’s formula and Rankine’s formula.

E = 0.7$\times$10⁵ N/mm², Factor of safety = 4, Rankine constant a = 1/1600, Crushing stress f_y = 567 N/mm².