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UNIVERSITY OF COLORADO STUDIES 



line VV is the chord of the neutral curve; verticals through the 

 centers of gravity of the parts into which the rib has been divided 

 cut the neutral curve at the points 1 to 18 inclusive. Lines like a h 

 above the rib indicate the limits of parts. The numbers at the top 

 of Plate I between these lines give the component and total weights 

 on the different parts of the rib. These weights or loads are assumed 



to act in the vertical lines through the points V, 1, , 18, V. 



Table I gives the results of the trial division of the rib into parts of 



lengths n. It will be noticed that— is essentially constant. 



TABLE I. 



For convenience a load line AB is laid off upon the vertical 

 through the left springing point. The parts of the load line, Al, 12, 

 etc., represent to scale the total loads dead and live acting at the 

 points 1, 2, etc., of the rib. A pole is selected at any point C whose 

 pole distance= 210,000 ibs., and rays CA, CI, etc., are drawn to the 

 points A, 1, etc., of the load line. The trial polygon BIJKB is 



