Moment Connections
Moment Connections
(OP)
Dumb question....no references around me presently....
Am I correct to assumed that endplate moment connections should have fully tensioned bolts?
Am I correct to assumed that endplate moment connections should have fully tensioned bolts?






RE: Moment Connections
RE: Moment Connections
RE: Moment Connections
I was under the impression that ALL bolts in tension connections must be fully pretensioned.
RE: Moment Connections
RE: Moment Connections
Use pretensioned bolts.
RE: Moment Connections
RE: Moment Connections
RE: Moment Connections
Throw away the code book for a minute and use that grey matter between your ears.
The analysis program will assume that this fully fixed connection will remain at 90 degrees even when everything else deflects. Now if you do not have a pretensioned bolt then how can the connection even remotely resemble this fixed state? As soon as you apply load to a snug tight bolt the plates will start to separate thus altering the connection angle.
RE: Moment Connections
I mentioned the code to provide a reference from the authorities on the subject. Obviously a long-winded explanation wasn't my goal.
RE: Moment Connections
RE: Moment Connections
BA
RE: Moment Connections
I don't use that. For all x-bracing and connections (typically end plated) stipulating both a shear and a moment, I use slip critical...
Dik
RE: Moment Connections
http://www.FerrellEngineering.com
RE: Moment Connections
http://www.FerrellEngineering.com
RE: Moment Connections
Pretension required for A490 bolts in combined shear and tension, regardless of fatigue. A325 bolts can be snug-tight.
http://www.FerrellEngineering.com
RE: Moment Connections
RE: Moment Connections
RE: Moment Connections
I would be interested to see that research as what you are saying to me is very counterintuitive.
Sorry if I came across a bit confrontational, I just get a bit edgy when people start automatically going code says.... e.t.c. are we engineers or code lawyers?
Also, you would be surprised at how different the codes of different countries can be on what you would think are well known topics. I have come across situations where two codes are mutually exclusive (i.e you cannot design something that meets both).
RE: Moment Connections
RE: Moment Connections
I guess, its the same thing that keeps your car/truck wheels from falling off!
RE: Moment Connections
Without inspection, how do you know you are getting pretensioned bolts? I agree that Slip-Critical is not necessary. But, inspection should be required for all pretensioned bolts, if not all bolting in general (IMHO). Most iron workers do not know the specifics of slip resistance and faying surfaces. The process for installing slip-critical and/or pretensioned bolts is the same. And the method of installation should be inspected.
http://www.FerrellEngineering.com
RE: Moment Connections
No problem. The point about code reciting is a valid one. I prefer to keep it short and sweet on here. I leave the dissertations to others.
AISC Design Guide 4 discusses the research and testing of end-plate moment connections, going back to the 1950s.
h
RE: Moment Connections
RE: Moment Connections
Per RCSC and AISC, the only difference between slip-critical and pretensioned is the required surface preparation for slip critical. Both require inspection per RCSC 9.2, dependent on the method of installation selected.
http://www.FerrellEngineering.com
RE: Moment Connections
RE: Moment Connections
RE: Moment Connections
You are correct,I think, that the current spec just looks at the faying surface.
nutte - thanks - I meant to say connection, not bolt.