KCCKNTKIC KIYKTKI) (ONNKC TIO.N. 



595 





78,650 



n - - - - 9 nvets. 

 9,190 



The number of rivets between C and web, B, is determined by single shear, and is 



m 73.340 + 54.920 + 91.530 - 1(90.500 + 44.450 + 78.650) 



7,220 



End Connections for I-Beams. The end connections for Carnegie I-Bcams are given in 

 Tulili-s 117 and 118, and for Bethlehem I and Girder Beams in Tables 156 and 157, respectively. 

 Tin- i-nd connections for short beams, and for beams carrying heavy loads should be carefully 

 i 1 1\ i->tigatcd for direct and bending stresses. Rivets should never be used in direct tension, 

 Connections where rivets would be in direct tension should be provided with turned bolts. 



Eccentric Riveted Connections. The actual shearing stresses in riveted connections are 

 ofu-n very much in excess of the direct shearing stresses. This will be illustrated by the calcula- 

 tion of the shearing stresses in the rivets in the standard connection shown in Fig. 15, which is 

 assumed as loosely bolted to a column. 



The eccentric force, P, may be replaced by a direct force, P, acting through the center of 

 gravity of the rivets and parallel to its original direction, and a couple with a moment M = P X 3 

 in. = 60,000 in.-lb. Each rivet in the connection will then take a direct shear equal to P divided 

 by n, where n is the total number of rivets in the connection, and a shear due to bending moment M. 



The shear in any rivet due to moment will vary as the distance, and the resisting moment 

 exerted by each rivet will vary as the square of the distance of the rivet from the center of gravity 

 of all the rivets. 



Now, if a is taken as the resultant shear due to bending moment in a rivet at a unit's distance 

 from the center of gravity, we will have the relation, 



M = a(df + df + <# + ^4* + dfi 2 ) 



and 



c = 



M 



The remainder of the calculations are shown in Table I. The resultant shears on the rivets 

 are given in the last column of the table and are much larger than would be expected. 



The force and equilibrium polygons for the resultant shears and load P, drawn in Fig. 15, 

 close, which shows that the connection is in equilibrium. 



TABLE I. 



