STRESSES IN A TRANSVERSE BENT. 



when the wind is acting as shown. Before solving the stresses at the joint 6-7-9 >t was necessary 

 to calc-iil. itc tin- stresses in members -li, 10-11 and 9~A. The remainder of the solution offers 

 no difficulty to one familiar with the principles of graphic statics. 



J..I 



Trusses 32-0 'c. fo c. 

 Dead Load '20 Ib. sq.ft.hcr. 

 MndLoad'20lb. - ' vert. 



000 10000 20000 



8 A 



WIND LOAD STRESS DIAGRAM 

 COLUMNS FIXED 

 (0) 



FIG. 3. 



The stress in post b-a is equal to V, while the stress in l-c is found by extending i-c to c' 

 in the stress diagram, c' being a point on the load line. The stress in post n-A is equal to V' t 

 while the stress in ig-m is found by extending ig-m to m' in the stress diagram, m' being a point 

 on the horizontal line drawn through C. The kind of stress in the different members is shown 

 by the weight of lines in the bent and stress diagrams. 



For a detailed discussion of the calculations of the stresses in a transverse bent, see " The 

 Design of Steel Mill Buildings." 



STRESSES IN BRIDGE TRUSSES. The stresses in bridge trusses may be calculated 

 by applying the condition equations for equilibrium for translation, resolution; or by applying 

 the condition equation for equilibrium for rotation, moments. Both resolution and moments may 

 be calculated algebraically or graphically, giving four methods for calculation the same as for 

 roof trusses. 



Maximum Stresses. The criteria for loading a truss or beam for maximum and minimum 

 stresses are given on page 160, Chapter IV. 



Problems. The methods of calculating the stresses in bridge trusses are shown by several 

 problems taken from the author's " The Design of Highway Bridges." 



