-^ I.I VM -LOAD STRESS i 



Th< formulas for 7?! and ft are the same n> formula- 

 (9) and (9a) for the Birder without panels, if the gird, r 

 bridge with panels has end floor-beams; but if this bridge 

 has end struts with the end stringers resting on separate 

 pedestals, the value of Ri beneath the end of the main 

 girder is the same as S a , the shear in the end panel, as 

 given by formula (17) to follow. 



Inasmuch as the maximum bending moment in a beam 

 carrying concentrated loads always occurs beneath a con- 

 centration, the maximum bending moments in the main 

 girder of a girder bridge with panels will occur at the floor- 

 beams. The influence line for the bending moment at the 

 floor-beams is the same as for the bending moment in a 

 girder bridge without panels; accordingly, formulas (10) and 

 (11) are to be used in finding maximum bending moment > 

 at the floor-beams. 



It remains to derive formulas for the maximum shears 

 S a in the end panel and S b in any intermediate panel. In 

 Fig. 6 are given the influence lines for S a and S b . The 

 correctness of the ordinates is at once evident. The slopes 

 and coefficients are calculated as explained in Arts. 2 and 3. 

 The general formulas for S a and S b and their rates of varia- 

 tion may be written at once by use of formulas (7) and (8). 



(17) 



- jJf4-M, + jf t -jJlfi ........ 



w <- w '+ w *- w * 



Formula (17) when compared with formula (10) 

 that S a is equal to the bending moment at the fir^t inter- 

 mediate floor-beam divided by the length of the first pawl. 

 Formula (18) when compared with formula (11) shows that 



