A325 Bolt Dimension Question

[Dinosaur]

I need to find a source for the standard shank and threaded run on A325 bolts. My AISC manual shows the head, nut and washer dimensions so I got that. What I need to know is for say a 2-3/4 inch long bolt, how much is threaded and how much is not. We have an installation under design that may need special order bolts for this reason, and I want to get the information to the designer so he understands. Thanks.

 

[whyun]

Per ASTM A325-04a (at the end, Supplementary Requirements):
Bolts with nominal lengths equal to or shorter than four times the nominal bolt diameter shall be threaded full length. Bolts need not have a shoulder, and the distance from the underhead bearing surface to the first complete (full form) thread, as measured with a GO thread ring gage, assembled by hand as far as the thread will permit, shall not exceed the length of 2-1/2 threads for bolt sizes 1 in. and smaller, and 3-1/2 threads for bolt sizes larger than 1 in.

 

[Dinosaur]

Thanks. I found some information in the AISC manual I didn't see earlier also. Dino

 

[RARWOOD]

When I review the Manual of Steel Construction Ninth Edition Specifications for Structural Joints Using ASTM A325 or A490 bolts, it appears to me that the specification permits full length threads on bolts with nominal lengths equal to or shorter than four times the nominal bolt diameter, but does not require it.

If full lenght threads were a requirement then the use of joints with threads excluded from the shear plan would not be practical in buildings constructed using structural steel.