EXTERNAL FORCES 



45 



In using the table first find the value of x by dividing the total 

 span by the distance from the nearest support to the load. Then 

 multiply the load by m in the table opposite the value found for 

 x. Do this for each concentrated load in turn, add the weight of 



Loading 



"^1 



w 



......... L ........ 



..... -1 



Maximum 

 Bending 

 Moment 



M-PL 



Relative 

 Strength 



Relative 



Deflection 



ntermaaf 



stress 



3.2 



2-4 



Q8 



0-4 



02 



Fig. 38 Reference Table Showing the Strength and 

 Stiffness of Beams 



the beam, and then find the bending moment for the total uniformly 

 distributed load so obtained. 



The method of equivalent uniformly distributed loads is 

 applicable only to bending moments. When a load is uniformly 

 distributed the end reactions are equal and the shear is always 

 equal to the reaction, so if the reactions and shears are considered 

 at each end as being one-half the equivalent distributed load the 

 beam may be weak in shearing resistance and the supports may be 

 improperly designed. It is necessary, therefore, to compute the 



