Axial vs. Flexural Bracing for CFS studs 3

[Revv]

Hey guys,

So when you brace your CFS studs, when do you consider it axially braced? I'm pretty familiar with the flexural bracing concept but not as sure about axial bracing. Could anyone point me in the right direction for this?

Thanks!

 

[phamENG]

Revv - is this question specifically for CFS studs or bracing in general? Nothing special about studs. Works the same as steel columns or wood studs, really. You need a brace with sufficient strength and stiffness and a load path. The load path is the thing most people don't bother with - if you have 20 studs and just put a strap across them, you haven't done much. Sure, it'll help with point loads where one stud is loaded more than the others. But if you have a uniform load that pushes them all to the buckling load, the bracing with no load path just ensures they'll all buckle in the same direction.

 

[milkshakelake]

Plywood or gypsum board wall sheathing plus bridging will make the minor axis braced in compression. Personally, I consider the weak axis unbraced length to be 4'-0" OC, which is the typical bridging spacing in my area.

Some other cases: Bridging only without wall sheathing is questionable, but doesn't really exist. Wall sheathing without bridging - I'd consider it unbraced in minor direction. When it comes to posts/columns, they're unbraced like with steel. Jambs, which are the end of a stud wall - I consider them unbraced, since they're the ones doing the bracing of the studs, but I think it's open to interpretation.

The major axis is generally unbraced for CFS studs except for rare special cases, which I don't think I've encountered.

 

[Celt83]

to illustrate what I believe phamENG is indicating by a sufficient load path:

 

[phamENG]

Thanks, Celt - that's exactly what I meant.