Do shear studs at top flange provide lateral support?

[BurgoEng]

I have a 6-story steel beam(&joist) with concrete slab and masonry bearing wall residential building with 2 levels of parking at bottom floors.

We are not considering composite action for the steel beams, and the concrete slab will not have a metal deck. I would like to use shear studs at the top flange of the steel beams to provide the lateral support required to keep Lb<Lu. Everything I have read about shear studs is in consideration of having the beams become composite, or to transfer shear (which I also want for transfering lateral wind loads through the diaphragm that is the floor slab), but I can't find anything specifically for shear studs used only to provide lateral support for KL/r, etc....

If I was to simply provide 3/4"studs @ 4ft, is that saying that the beams would be having a laterally unbraced length of 4ft?

 

[Qshake]

If you're concerned about providing lateral support for the beam while placing the concrete deck/slab, then no, the studs will not provide any lateral support. However, a quick remedy is to use temporary bracing.

If you're considering the lateral support after the deck is in place then yes. Of course, you could also use a slightly deeper slab down to the bottom of top flange to help also. This is more widely used in bridge practice than building practice.

Regards,
Qshake

Eng-Tips Forums:Real Solutions for Real Problems Really Quick.

 

[BurgoEng]

Qshake,

I am concerned about after pouring the slab, and for the life of the building, not during construction. I had thought about extending the slab to the bottom of the top flange as well, but I think this detail won't be worked out until the joist manufacturer is determined. Some have wanted to use Hambro joists in which case i believe embedding the top flange would be no prob, but otthers want to use conventional open web joists in which case extending the concrete may case too much of a forming issue. then again, if we used conventional, shear studs wouldnt be able to be used because the bottom of the slab would be 2 1/2" above the top flange....hadnt thought of that.

 

[dik]

Once the deck is in place with the hardened concrete, lateral support is provided by the topping slab.

Dik

 

[apsix]

Shear studs will work, but so will cheaper items such as rebar offcuts, short bits of Flat bar or Angle etc.

 

[Dinosaur]

BurgoEng,

This is a straightforward question you should discuss with your supervisor. Use of studs and bracing compression flanges is well understood.

Good Luck

 

[BurgoEng]

If I had a typical structural supervisor and supoprting cast of characters I could go to I'd do that, but unfortunately, I don't really have that available to me so I am on my own to figure a lot of this stuff out. Which brings me to this site more often than not.

 

[twinnell]

BurgoEng,

The current construction practice for this type of building is either concrete construction up to residential levels where wood framing is provided on a concrete table top, or concrete construction with mild reinforced slabs or post tensioned slabs (post tensioned usually cheaper), or steel framing with composite deck. A cost analysis between composite deck and joist supported deck would probably show that the composite deck is more economical.

Why aren't you using metal deck for your slabs? Are you shoring all of your slabs?