Cold Formed Steel: Simple Clip Beam Connection Design

[KirkGH]

For architectural reasons it's better to turn the cees in the direction shown in the attached document. My concern is buckling of the clip angle. Is this wise? How do I calculate the capacity of the clip?

As best I can tell I could approximate the condition conservatively as a cantilever to get my M. V is obvious. Then go through the AISI manual (CRINGE) and get an allowable M and V and check combined shear and bending assuming section properties are that of a rectangle.

Any easier way? My easier way, right now, is to turn the cee the opposite way shown, frame in the cee with a simple clip angle and then attach a 20 gage track to the outside face to give a smooth profile.

Details B and C show two ideas on a bearing connection. Is a bearing plate required? If not is detail C correct? I'm going to frame into the side of the tube but the architect may question if we can sit on top. There's a 1/2" in 12" slope not shown.

Finally, does anybody know where I can find design examples and typical details? I know there's a reason why most companies use computer software for light gage steel design but that's not an option at this point in time. I've got AISI Spec, AISI Manual, and Cold Formed Steel Design by Yu, Wei-Wen. There's good stuff but nothing quite like what I'm hoping to be directed towards.

I appreciate your time.

One last thought. Both my supervisors, when approached independently, say for the small stuff I'm doing I can pretty much follow AISC to get capacities. What do you have to say about that? Personally, I just got my license and haven't wrapped my brain around a lot of stuff and I'm not quite comfortable putting my seal on something I didn't hammer through exactly by the book.

KGH

 

[wannabeSE]

I can't tell from your sketches what is being connected. I do not see how B and C relate to A. From you description, I am guess in want a connection similar to the floor opening detail shown on detail F24 (pdf page 40) of the Low Rise Construction Details that can be downloaded at

http://www.cfsei.org/details/PDF/Low-Rise Residential Construction Details.pdf

.

 

[wannabeSE]

Sorry for the bad grammar above. I meant to hit preview and submitted the post instead.

 

[hokie66]

In your detail A, turning the supporting channel around is the correct way. That way, you are loading it nearer to its shear centre, thus decreasing twisting. That connection is also much more compact, so requiring less attention to the bending in the connection. As to details B or C, it can be done either way, and the best detail would depend on the loading.

 

[XR250]

Detail A is not a great detail. You have to resist the eccentric moment in the screw group.
800 lbs is not significant, however. Prolly a 10ga clip and enough screws and you will be fine.
You could also cope the flanges of the 12 ga stud so it can nest into the intersecting stud.
Then you can simply use clip table from Dietrich or the steel network.
Your 20ga track idea is probably the best

 

[KirkGH]

wannabeSE: Detail A is independent of B and C. They are two separate questions: Thanks for the link.

I've looked further into the required bearing condition and it looks like AISI 2001 Eq. C3.4.1-1 web crippling capacity calculation is only valid for bearing lengths >= 3/4". This eliminates detail C as an option. The moral of the story continues to be stick to the charts.

Thanks for the input.

KGH