86 LOADS IN STRUCTURES 



The economy obtained by this disposition of the live load is 

 observed from the following table, which gives the dis- 

 tribution of the assumed live loads on the columns in the 

 several tiers of an eighteen-story office building. 



REDUCTION OF LIVE LOADS FROM FLOOR TO FLOOR 



The following may serve to explain the data given in the 

 table: a represents the live load on each floor, in pounds 

 per square foot; a\ the live load on each floor, in pounds 

 per square foot, reduced by 10%, as ai = .90 a; 2a, the sum 

 of all live loads, in pounds per square foot, on a column 

 from all floors above, if no reduction is made; and 2aj, the 

 sum of all live loads, in pounds per square foot, on a column 

 from all floors above, if 10% reduction is made. 



The theoretical percentage of saving resulting from the 

 reduction of 10% on the upper floors is found by the for- 



2a 2aj 

 mula - . These percentages of saving are given in 



the last column of the table. 



