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CAMBRIA STEEL. 



STRENGTH OF STEEL COLUMNS OR STRUTS. 



For various values of - in which L = length in feet and r = 



radius -of gyration in inches. 



P = ultimate strength in Ibs. per square inch. 



FOB SOFT STEEL. 



Square bearing Pin and square bearing Pin bearing 

 45 000 45 000 45 000 



P = 



1 + 



1 + 



(12 L)* 



(12 L)* 



36 000 r 2 ' 24 000 r 2 ' 18 000 r 2 



To obtain safe unit stress: 



For quiescent loads, as in buildings, divide by 4. 

 For moving loads, as in bridges, divide by 5. 



