Double-Sided End-Plate Bolt Sharing

[seistructure2]

Are there any limitations on bolt sharing in a double-sided end plate connection, typically where 2 beams are connected to a column web? I recall that I read somewhere in a code that some structural system forbids the use of shared bolts, although I cannot find the code that states the limitation.

 

[DanKile]

They can share bolts, but you need to provide at least one unshared bolt, possibly for each beam. This is so the weight of the beam can temporarily hang from the one bolt until the other beam can be installed. In the USA this is covered in OSHA.

 

[JoshPlumSE]

Are there any limitations on bolt sharing in a double-sided end plate connection, typically where 2 beams are connected to a column web? I recall that I read somewhere in a code that some structural system forbids the use of shared bolts, although I cannot find the code that states the limitation.

Yes, like DanKile shared, this is an OSHA restriction related to the safety of workers during erection of the beams. There are ways that contractors can work around this issue... Usually they involve offsetting the two end plates (or doubles angles or whatever) from each other so that on beam is stable with only a couple of bolts, while the other beam gets swung into place.

 

[seistructure2]

Thanks for the reply. Do you know which OSHA document that is? I'm not familiar with that, as OSHA is not widely used in my country (though we adopt the AISC for steel code).

And if we're designing in a high seismic region, is there any effect of high lateral load on the shared bolts? Say where the connection is used for SCBF system.

 

[DanKile]

It is section 1926.756(c)(1) in OSHA 1926 Construction.

Skimming through AISC 341, it does not appear that there is any additional requirements for this joint. You should review this for your self to see if there is something applicable.

 

[JoshPlumSE]

If your country doesn't use OSHA for worker safety standards, then this doesn't really apply to you. Heck, it was only maybe 15 years ago when OSHA added this for the US.

 

[seistructure2]

Thanks, DanKile. I'll check the OSHA for more info.
Yeah, 341 didn't mention any about the bolt sharing. My thought was that if the 2 beams experience flexure/tension simultaneously, the shared bolts will have to resist 2 different tensions and flexures, increasing the loads. Though I need some insight about this, whether I can neglect and move on, or consider the shared loads.

 

[seistructure2]

If your country doesn't use OSHA for worker safety standards, then this doesn't really apply to you. Heck, it was only maybe 15 years ago when OSHA added this for the US.

Ha, regardless, the example you post is practical and logical. Maybe I'll learn something (hopefully, a lot) from the OSHA.