Lateral Supports For The Building

[FiniteElemet]

Hi,

Have a 60x40 building with roof trusses bearing on perimeter beams.
Beams are provided all around the building for truss bearing and lateral support. Can the infill cold-form studs between HSS columns supporting beams be considered ample for the lateral support of the structure or shall I be looking at additional structural members for lateral stability. Eave height is 12 ft with wind load of 22 psf and for ease assume column loads as 10 kips vertical/2kips Horizontal.

Thanks in advance for responding.

 

[BAretired]

Cold-form studs do not provide shearwall strength on their own, but the cladding attached to them may be adequate. My preference would be to consider the wall non structural, then provide adequate bracing without relying on the stud wall but many would disagree.

BA

 

[XR250]

I do a bunch of light gage design and I am with BAretired on this one. Even though it is possible, the quality of light gage framing is usually sub-par so whatever you detail will likely not get installed as intended. Most jobs I see with type of framing have a diagonal tube steel brace periodically between columns interrupting the light gage framing.

 

[CANPRO]

Also, some people don't seem to have a problem removing x-bracing if it gets in the way...I doubt they're going to consider the effects of putting extra garage doors in your shear walls.

Though, your building isn't all that large. Maybe look at using a couple of interior walls too?

 

[MJB315]

Remember to design the steel bracing for out-of-plane loads if you interrupt and connect the light gauge studs to them.

"We shape our buildings, thereafter they shape us." -WSC

 

[madmantrapper]

I witnessed a guy cut the cross bracing once. It was a pair of 1 1/2 rods with turn buckles. He cut one with a torch and the bars jumped about three inches apart. Quite frightening.

 

[MikeHalloran]

<tangent>

A guy contracted to build a small array of bathrooms inside our factory, based on using ~26 gage galvanized framing, which is easily pierced with a hard pointed thread forming sheet metal screw.
His supplier 'did him a favor' and supplied 16 gage galvanized framing, so the poor guy had to predrill for every damn screw. It took him an extra two days.

A quick search has found design guides for 'standard' steel framing in gages from 12 to 24 including most even numbered gages between.

Do you specify a particular gage when you design light gage steel framing?
If not, perhaps you should consider doing so.

</tangent>



Mike Halloran
Pembroke Pines, FL, USA

 

[XR250]

@Mike,
Modern Tek screws easily fasten 16ga or heavier material in seconds. No drywall contractor with 1/2 a brain would use anything but.

 

[IsaacStructural]

@mike, yes specifying the gauge of studs is standard procedure. Typically we specify the shape, gauge and spacing. Often non "structural" walls, still require our attention, for example, a 20 foot wall entryway wall. It may not be a part of the buildings main lateral or gravity load system, but it still needs to be stiff enough to not sway or damage under wind loading. In that sort of case we'll be looking at tightening the stud spacing, using heavier gauge, deeper studs, or some combination.

Licensed Structural Engineer and Licensed Professional Engineer (Illinois)

 

[msquared48]

@ Mike:

Besides the gage, you should always spec the Fy and minimum allowable section properties (A, S, I) of all the structural members used due to preferences of different contractors in using different light gage steel manufacturers.

Mike McCann
MMC Engineering

 

[Jerehmy]

http://cad.clarkdietrich.com/CAD_Index.php

useful details for cold form framing.

 

[XR250]

@Msquared:

If you specify using SSMA nomenclature, it is not an issue as everything is pretty much standardized around that.
For instance, for a 6", 1 5/8" flange, 18ga structural stud, I will specify 600S162-43.

 

[msquared48]

Right, but some have a turn on the end of the C, and some don't. Over the years, I have seen all sorts of different nomenclature and have just gotten into the habit. No worries.

Mike McCann
MMC Engineering

 

[TDIengineer]

You may be able to use 18 gauge studs with plywood sheathing as your lateral element. They have ICC reports now for plywood over metal studs.