Steel Stud Wall at Steel Beam

[NewbieStruct]

I recently had gone to a job site to measure some existing joists since we are going to have some new mechanical units on the roof. The steel beam supporting the joists has some vertical steel studs at the exterior. They are not sitting on the beam flange but they are attached (welded) to the beam with angles (cont. one each at top and bottom of the steel stud). Also these steel stud walls seem to have channels at about 4'0" o.c within the wall at the openings (window/door) in the steel stud wall. The end of the openings themselves are supported on steel channels. I am just wondering whether this scenario would introduce any dead load on the steel beam or these loads due to the stud walls will go directly to the foundation. Does it depend on how the construction sequence was?

 

[BAretired]

Perhaps. Provide a cross section of the detail.

BA

 

[Ron]

Agree with BAretired...sketch would help.

If I understand your description, not only will you have dead load on the beam from the studs/wall/doors/windows, but you might have torsion on the beam as well since you imply that the angles are welded away from the centerline of the beam.

 

[NewbieStruct]

Sorry for not replying before - had to deal with a family crisis.

I am attaching a sketch as per the site condition.

 

[structSU10]

I would be worried about the interaction there a little. Normally something like that would be a vertical slide clip to make sure any deflection in the beam doesn't affect the wall and such. As the beam deflects do to any load, it will try to transfer force through that angle to the stud wall / frame, which could be damaging.

 

[BAretired]

If the studs are supported at foundation level, they will prevent the steel beam from deflecting, so the beam could be loading the studs. In a fire situation, the studs would expand and either lift the beam or buckle.

If the studs are not supported by foundation, they will hang eccentrically from the beam causing flexural and torsional stresses in the beam.

BA

 

[NewbieStruct]

The studs are supported at the foundation level in between the openings. The openings are supported by steel channels which in turn also go to the foundation.

I am looking at adding a mechanical unit on roof that is supported by the wide flange beam. Do I need to worry about the beam ?

 

[structSU10]

the channels will act as a point of support for the beam, with the angle as the load path. This will be an issue for any kind of load on the roof, be it dead, snow, live etc. That connection should be a slip type connection unless it has been designed to take the load, which i highly doubt.

Try to model the situation if you must, but i would think that angle should be taken out and some sort of clip that allows vertical movement be installed in its place. This all depends on how it was designed in the first place though.

 

[shobroco]

I think contrary to modifying it to allow it to deflect, you should be loooking at the cpacity of the channels as columns which increase the ca[acity of the beam, even allowing for torsion. I imagine that you'll find the original designer sized the beam without the support of the channels,it was built as you see it, and this has actually increased the structural capacity. That doesn't mean that the joists sitting on the beam can carry your new load.