COOPER'S CONVENTIONAL ENGINE LOADINGS. 



159 



OOOO o o cm zo OOOO noon 



Class 



E-40 





t $' 'J/ic^ir^i^ 



UniFormLoid 



11 



4000lb- 

 perlirr-Ff- 



E-45 



I 1111 



5 





a 



4SOOIb- 

 per /it?- ff- 



50 



1 1111 I 



I 1 |1 |l 



SOOOlk. 

 per I in- ff- 



E-55 



111 





1111 



S*S ^ *<\ *<\ 

 **c^ *<% Vc\ Wv 



SSOOIb- 



l-SO 



1 1111 



11 11 1 



11 



1111 



6000/b- 

 per/ifr-ff- 



FIG? 1 8. COOPER'S CONVENTIONAL ENGINE LOADINGS. 

 (Loads for one track.) 



Equivalent Uniform Load System. The equivalent uniform load for calculating the stresses 

 trusses and the bending moments in beams, is the uniform load that will produce the same 

 bending moment at the quarter points of the truss or beam as the maximum bending moment 

 produced by the wheel concentrations. The equivalent uniform loadings for different spans for 

 Cooper's E 40 loading are given in Fig. 19. The equivalent uniform loading for E 60 loading 

 will be f the values for E 40 in Fig. 19. In calculating the stresses in the truss members select 



"? 8500 



E 8000 



S 7500 

 o 



"*" 7000 



Both 



O 

 "? 



8 



1 Load 



m O 

 V O 



88 



5000 



D 



4500 

 j> 



.% 4000 



?00 



u 



20 40 60 60 \00 120 140 \W) \QQ 200 220 240 260 



5pan of Bridge in Feet 



FIG. 19. EQUIVALENT UNIFORM LIVE LOAD FOR COOPER'S 40 LOADING. 

 (Loads for one track.) 



the equivalent load for the given span, and calculate the chord and web stresses by the use of 

 equal joint loads, as for highway bridges. In designing the stringers for bending moment take a 

 loading for a span equal to one panel length, and for the maximum floorbeam reaction take a 



