Stiffeners per section J10.7

[sshields]

Hello everybody,

I have a wide flange beam end bearing atop a HSS column. The connection is transfering a moment, and has been checked for several of the criteria in section J10 and K. There isn't a need for stiffeners for strength purposes, but I read the code in section J10.7 to say that I need them for stability.

In that case, can the criteria that I use to size them be the 3 listed on top of page 16.1-121?

Secondly, I belive that I only need one pair centered on the column center line. Or would I place 2 pairs, each centered above the HSS wall. (See sketch)? I ask this question because I've seen both done before, but don't know if they were placed for strength purposes or stability.

http://files.engineering.com/getfil...1-7704-4719-8612-44ef334f3511&file=sketch.pdf

Thank you everyone in advance.
Scott

Scott

 

[a2mfk]

Without looking up that criteria, stability of the top/bottom flanges of the beam or the column or both? I'm guessing its more for the column because bracing to the compression flange(s) of the beam may be provided by other means.

No matter the answer, I see no need for more than one stiffener if it is only for stability, and I can't think of a reason why the exact location would matter so I would center it.

But I am sure someone else will have more info on that...

 

[sshields]

The stability criteria is two fold -

First - You don't want the beam to be able to rotate about its longitidunal axis.

Second - Follows from the first, if the column was designed as fixed - pin, then we need to stiffen the top such that it performs as if there was a pin.

Or thats at least how I understand it.



Scott

 

[ToadJones]

I would located the stiffeners over the HSS walls as in figure two.
With the beam in strong axis bending, the column will be delivering concentrated forces to the bottom flange of the beam. These forces will be highest at the HSS walls.