SIMPLE TRUSSES g 



All of the demonstrations given for Fig. 1 apply to Fig 2 

 For all loads upon the left of the vertical through G the 

 vertical is in tension and for those upon the right of G 

 it is in compression. 



Web Member of Warren Truss with Inclined Top Chord 



The web member U'L, Fig. 3 has been selected A 



comparison with Fig. 1 shows that the influence diagram 



= ( W* + W,')j,. 



FIG. 3. 



is constructed in exactly the manner followed in Fig. 1, 

 and that all of the demonstrations of Fig. 1 apply equally 

 well to Fig. 3. The locations of points m and m' are 

 clearly shown in the figure where the verticals h and h' 

 and the diagonal UL f are not members of the truss. 



Web Members in Simple Trusses Having Parallel Chords. 

 The case shown in Fig. 4, presents an apparent exception 

 to the general rule for drawing the influence line DEFB. 

 The center of moments for any web member of a truss 

 having parallel chords is at infinity. Taking N, the left 



