W Shapes to HSS Columns

[savage250]

I'm looking for a guide to designing connections (shear and shear/axial) connections to HSS columns.

The Canadian guides are very simplistic, basically checking punching shear for a shear tab, and that is all.

Does anyone have any suggestions?

 

[tolchijb]

Chapter K of AISC provides guidance for HSS connections.

 

[JAE]

We use single plate shear connections.

 

[savage250]

Part of my question is when you add a plate behind that single plate shear connection because the column wall isn't thick enough for the shear/axial loads from the beam or beam & brace, how do you design that plate?

Also when you have a large shear force in a beam into the side of a HSS column, how does that force entering in wall distribute to the entire HSS section?

 

[Ltwine]

Unless the stresses are low, I will avoid this type of connection. Use HSS-HSS, WF-WF, or let WF sits on HSS would be better choices.

Check AISC publication on design of HSS connections.

 

[LowLax]

Single plate connections are popular in my neck of the woods. I usually just make sure my HSS walls are not slender elements. AISC 13th Ed. Manual, pg. 10-158 says: "As long as the HSS wall is not classified as a slender element, the local distortion caused by the single-plate connection will be insignificant in reducing the column strength of the HSS."

If you have a slender wall you probably should use a through plate connection.

pg. 1-93 has a handy chart for compactness criteria.

 

[savage250]

I also should have mentioned I am a steel fabricator, so we don't have much choice when it comes to members. It's a typical detail for a beam to frame into relatively light HSS column that continues through the beam to the next story.

Then you add a braced bay to that, and I have a large amount of forces to be connected taht need to pass through the HSS. I do use through plates sometimes, but sometimes I wonder if it's really necessary or not.

My rule of thumb so far has been if the column is "slender" to reinforce with a plate behind the shear plate if just shear, and to use a thru plate if there is axial load in the beam.

I was wondering if anyone else had a reference guide or text they used to further refine the design.

Thanks for the replies so far

 

[msquared48]

For beams on opposite sides of the column, I just use a single through-the-HSS Knife Plate. I would do this for the most heavily loaded beams.

Beyond that, I would use a knife plate welded to the center line of the HSS with a horizontal stiffener top and bottom.

Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask

 

[Ltwine]

Check out "Hollow Structural Sections - Connections Manual" by AISC & Steel Tube Institute. It may help.

 

[BAretired]

"Hollow Structural Section Connections and Trusses" by J.A. Packer and J.E. Henderson is published by CISC and is a good reference.

Tests have shown that there is no advantage to using through plates as opposed to shear tabs if the column is Class 3 or better. For thin-walled HSS, through plates may be necessary.

BA