80 



STEEL OFFICE BUILDINGS. 



CHAP. II. 



where / = effective length of members in inches, 



r = corresponding radius of gyration of section in inches. 



For ratios of l/r up to 120, and for greater ratios up to 200, use the amounts given in the 

 preceding table. For intermediate ratios, use proportional amounts. 



A comparison of several compression formulas is given in Table IX. 



TABLE IX. 



COMPARISON OF COMPRESSION FORMULAS. 



ALLOWABLE UNIT STRESSES IN POUNDS PER SQUARE INCH. 



American Bridge Company. 



