CONSOLIDATED STEEL CORPORATION 



93 



A comparison of this formula with the column formulas specified by the 

 building laws of the principal cities in the United States is shown by the dia- 

 gram herewith, from which it will be seen that it represents about an average 

 of general practice. 



A riveted column, having the metal in its shaft injured and weakened by the 

 punching of numerous rivet holes, is liable to fail under a less load than a rolled 

 column in which the shaft is devoid of rivets. The formula does not take into 

 consideration this advantage in favor of the rolled steel column sections. It 

 represents only the best current practice in general steel column design and is 

 not limited to columns of special or superior shape. 



Safe loads computed by this formula are given in the tables on pages 100- 

 107 and 114-121 for all the sizes of Bethlehem Rolled H-Columns and on pages 

 96-99 and 110-113 for Bethlehem I-Beams and Girder Beams when used as 

 columns. The column required for any given load and length is readily selected 

 from these tables. 



The unsupported length of a column should not exceed 150 radii of gyra- 

 tion, which is the limit of length for which safe loads are given in the tables. 

 In the best practice the unsupported length of a column is frequently required 

 not to exceed 125 times the least radius of gyration; this latter limit is indi- 

 cated in the tables by zigzag lines. 



