Jl LINK-LOAD STRESSES 



For equal span-. /, = ^ = /. > that 



g. *.+*-"* (15a) 



Iii the la-t member of formula (15) the quantity within 

 the parentheses is the same as the expression for -g- in 



formula (11). It follows, therefore, that the same position 

 of loading gives maximum R and maximum M for any 

 given values of li and h> 



Problem. (a) Find the maximum pier reaction per rail 

 between two simple beam spans Zi = 10 ft. and 1* = 30 ft. 

 (6) Find the maximum pier reaction between two simple 

 beam spans, each having a length of 20 feet. Use Cooper's 

 50 loading. 



Solution of Problem (a). 



I -o formula (15) to find position of loading for 

 maximum R. 



'" 



// at ])'ur. 



Maximum. 



,. , 30,, 



(145) + (0) - * 



Use formula (14) to compute the value of R. 



- 37.5) = + 

 Maximum. 



(.!!! i "i. -'>) + : (12.5) -02.5) = - 



dz ' 10 X 30 \40 40 



