32 STANDARD SPECIFICATIONS 



even though the computed stress is less, the kind of stress to 

 which the member is subjected being considered. 



137. Riveted Work. (See Par. 90.) 



138. Rivets. In proportioning rivets their nominal diameter 

 shall be used. Rivets shall generally be in. in diameter, and 

 no rivets, except in lattice bars, shall be less than f in. in 

 diameter. 



The diameter of the rivets in any angle carrying a calculated 

 stress shall not exceed one-quarter (J) the width of the leg through 

 which they are driven. In minor parts f-in. rivets may be used 

 in 3-in. angles and f-in. rivets in 2i-in. angles. 



Rivets carrying a calculated stress and whose grip exceeds 

 four diameters shall be increased in number, at least 1 per cent 

 for each additional f& in. of grip. 



Rivets carrying stress and passing through fillers shall be 

 increased 50 per cent in number, and the excess rivets, when 

 possible, shall be outside the connected member. 



Rivets connecting flanges and lattice bars shall have sizes 

 as follows: f-in. rivets in flanges 3 in. wide and over, f-in. rivets 

 in flanges from 24 to 3 in., and f-in. rivets in flanges less than 

 2^ in. wide. 



139. Rivet Spacing. The minimum distance between cen- 

 ters of rivet holes shall be three diameters of the rivet and, if 

 possible, not less than 3 in. for J-in. rivets and 2J in. for f-in. 

 rivets. The maximum pitch, in the direction of the stress for 

 members composed of plates and shapes, shall be 6 in. for J-in. 

 rivets and 5 in. for f-in. rivets. For angles with two gauge 

 lines and rivets staggered the maximum shall be twice the above 

 in each line. 



Where two or more plates are used in contact, rivets not more 

 than 12 in. apart in either direction shall be used to hold the 

 plates together. 



In tension members composed of two angles in contact a pitch 

 of 12 in. will be allowed for riveting the angles together. 



The maximum pitch at ends of built-up compression mem- 

 bers shall not exceed four diameters of the rivet for a length 

 equal to two times the width of the members. 



140. Edge Distance of Rivets. The minimum distance 

 from the center of any rivet hole to a sheared edge shall be 1^ in. 

 for J-in. rivets and 1} in. for f-in. rivets, and to a rolled edge 



