MECHANICS 



119 



for usual cases. In Case XX, two values are given &r 

 both shear and bending moment, and the maximum of the 

 two values obtained must be the one used. The sign of 

 the shears or bending moments has not been put in the table, 

 but it can be told by inspection whether they are positive 

 or negative, as every-day experience should enable the engi- 

 neer to determine whether the loads will bend the beam up 

 or down. 



The point of maximum shear is marked on the beam at 

 the point a, while maximum bending moment is at the 



REACTIONS FOR CONTINUOUS BEAMS OVER EQUAL 

 SPANS 



(Coefficients of W) 



Num- 

 ber of 

 Spans 



Number of Each Support 







3d 



ttf 



III 



A 



ft 



H 



^ 

 m 



5th 6th 7th 8th 9th 10th 



m 



y;; 



m 



Ili,? 



Mi 



iiiii 



point b. In some cases, either of these values may reach 

 its maximum at two or more places, in which case it is so 

 marked. 



The following example will serve to show the use of the 

 table: 



EXAMPLE. A simple beam on a span of 13 ft. 2i in. carries 

 a uniformly distributed load of 85 Ib. per ft. What is the 

 maximum shear and the maximum bending moment devel- 

 oped? 



