Stiffener for eccentrically loaded Column Flange 2

[StuSE]

Hey you guys;

I am loading a structural column eccentrically for connections for the cladding of a building. This will cause rotation and bending in the column flange. I'm familiar with the web stiffener provisions, but am trying to determine at what point I need to add a flange stiffener to keep the flange from being overstressed.

Perhaps a simple bending analysis of 'x' width of flange would be appropriate, but I wouldn't mind pointing my finger at something specific. Do you guys have any tips?

Stu

 

[a2mfk]

Reminds me of a connection I designed once where a HSS cantilevered up from a WF beam. When I was in the field reviewing the connection, I was surprised by the amount of torsional movement in the WF when I applied a small amount of back and forth force to the cantilevered HSS. Though it ended up being ok, I would have added stiffeners if I had to do it again. Though a member may be OK in overall torsional strength, the local deformations in a WF may translate to a large amount of movement at the end of the cantilever.

So BA's math seems right if you were strength of the bottom flange were the only concern, but the localized moment is transferred from the web into the flange, and the deflection of both of these plate elements causes a rotational movement of the WF column which may produce an undesirable/unacceptable amount of lateral movement at the end of the HSS at your cladding connection.

I think I agree with BA, a stiffener plate on either side would properly transfer the torsional couple into the WF. I think you could shorten your HSS to terminate in line with the web of the WF and then put the stiffener on the near side, that way you are not loading the other side of the flange and I don't see a reason why you'd need to stiffen it.

This is a bit unusual of a connection so sorry if I missed something...

 

[hokie66]

Facade connections should be concentric or braced. I would connect it both sides of the column.