44 



Pin Plates. 



Maximum Length. 



Splices. 



Splices. 



Tension Members. 



Eye-Bars, 



Pins. 



SPECIFICATIONS 



For 8 and 7-inch channels, or 

 built sections with 2^/2 -inch 

 angles. 



For 6 and 5-inch channels, or 

 built sections with 2-inch 

 angles. 



2 inches 



rivets). 



inches (^2-inch rivets). 



Where laced members are subjected to bending, the size 

 of lacing bars or angles shall be calculated or a solid web plate 

 shall be used. 



73. All pin, holes shall be reenforced by additional mater- 

 ial when necessary, so as not to exceed the allowable pressure on 

 the pins. These reenforcing plates must contain enough 

 rivets to transfer the proportion of pressure which comes upon 

 them, and at least one plate on each side shall extend not less 

 than 6 inches beyond the edge of the tie plate. 



74. No compression member shall have a length exceed- 

 ing 125 times its least radius of gyration for main members, nor 

 150 times its least radius of gyration for laterals and sub- 

 members. 



75. In compression members joints with abutting faces 

 planed shall be placed as near the panel points as possible, and 

 must be spliced on all sides with at least two rows of rivets on 

 each side of the joint. Joints with abutting faces not planed 

 must be fully spliced. 



76. Joints in tension members shall be fully spliced. 



77. Tension members shall preferably be composed of 

 angles or shapes capable of taking compression as well as 

 tension. Flats riveted at the ends shall not be used. 



78. Main tension members shall preferably be made of 

 2 angles, 2 angles and a plate, or 2 channels laced. Secondary 

 tension members may be made of a single shape. 



79. Heads of eye-bars shall be so proportioned as to de- 

 velop the full strength of the bar. The heads shall be forged 

 and not welded. 



80. Pins must be turned true to size and straight, and 

 must be driven to place by means of pilot nuts. 



The diameter of pin shall not be less than J4 of the depth 

 of the widest bar attached to it* 



