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Bolts In Bending

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ToadJones

Structural
Joined
Jan 14, 2010
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Are there any provisions for checking bolts in bending?

I have a goofy connection which resembles a double-shear connection where one ply of steel is nested between two outer plies however, the plies are not tight together.

The bolt is essentially a simply supported beam with a point load at the center. I know this is not a good set-up but it's what I have to deal with at this point.

 
I have had to check bolts for bending numerous times because of joint geometry or a non-bearing material between the bolted fixture and the bearing fixture and I just analyzed them as circular beams; probably conservative because as soon as they bend they begin acting in tension.
 
Most codes have separate provisions for pins. Even if the plies don't have gaps, bending is present.
 
Toad
As you know a structural bolted connection (RCSC) requires all plies in firm contact. I would not recommend using a quenched and tempered structural bolt in your condition. The hardened material lacks ductility. Bending will lead quickly to fracture. You can use an A36 threaded rod. This would also be easier to analize for bending.

 
I'd suggest custom bolts that were actually pins with threads on both ends.
 
Can you fill the gap with washers?

Dik
 
There are some mechanical engineering texts that will provide you with a procedure to determine bolt bending moments. It will consider each plates thickness. The bolt, in this case, would now be considered a pin.
 
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