Steel Connection Design: Gap Between End of Beam and Column Flange 1

[GearsNsparks]

Howdy,

I'm looking at a bracing connection for some existing mining equipment structures. There is a nominal gap of 1/2" between the end of the beams and the connection to the flange of the column. Is this a common practice? Is it intended to help with manufacturability (getting the columns spaced exactly as intended without letting the cut beam length govern the spacing?). Or does this allow some sort of rotation to assume a pinned connection in structural analysis even though it looks like you could still transmit a healthy moment via the top and bottom beam flanges?

Thanks for any insight.

 

[bootlegend]

Are you sure there isn't a pair of angles missing from the sketch? It would be a pretty typical connection then.

 

[StrucPEng]

The gap is pretty standard for erection of the structure. Bootlegend is right in that there most likely is some sort of angles or shear plate connecting the web of the beam to the face of the column. (Photo per. AISC Detailing Manual 3rd Ed.)

 

[GearsNsparks]

I'm pretty sure there are no clips on the beam web. Uploaded the best picture I had from the site visit.

 

[T_Bat]

I second that 1/2" gap is pretty standard. Looks like an unstiffened seat connection to me. They are common - see part 10 of the AISC steel manual. They usually are installed with some nominal attachment to the web for stability purposes but I would imagine the welded gusset takes care of that.

 

[GearsNsparks]

Ahh roger that T_Bat. Looking at AISC part 10 page 84. Thanks!

 

[CANPRO]

The 1/2” is for erectability. If you don’t leave a gap, you’d be fighting with half your beams to get in place.