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Table VI. — Safe load on square columns of longleaf pine (Pinus palustris), 



[Load given in tons of 2,000 pounds.] 



Table VI gives the total safe load for square columns of longleaf pine 

 in tons of 2,000 pounds per square inch. 



In designing, one-half inch is to be added to each cross-sectional 

 dimension obtained from these two tables to allow for weathering. 



The ordinary column formula? take this form: 



/ 



F 



1 + 



a 



f— allowable working stress per square inch for the long column. 

 F= allowable working stress per square inch for the short column. 

 a = constant, for square-ended columns, usually taken at from 500 to 550. 

 I = length in inches. 

 d — least cross-sectional dimension in inches. 



From experiments made upon about 50 columns by this division, the 

 following formula may be deduced, which closely coincides with the 

 mean of the plotted points as shown on rig. 1. 



/ = 



F 



1 + 



700 + 15 ( -j 



G) 



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