Steel Beam Over Concrete Column/Wall Connection
Steel Beam Over Concrete Column/Wall Connection
(OP)
I have a situation where I have a steel beam over a concrete column. The attached sketch shows the connection. I am trying to make it a moment connection at the top, however my moments are quite large. I was wondering about the possibility of it not being a moment connection. I would really appreciate any opinions on this.
I also have the case of a cantilever steel beam over a concrete wall. The sketch shows am embed plate in the concrete wall. How adequate would this moment connection be.
Thanks for your help.
I also have the case of a cantilever steel beam over a concrete wall. The sketch shows am embed plate in the concrete wall. How adequate would this moment connection be.
Thanks for your help.






RE: Steel Beam Over Concrete Column/Wall Connection
You don't need a moment connection over the column, if the beam has sufficient capacity to do it by itself. In essence, the moment at the top of the column will be zero (pinned end).
The same concept will apply to the cantilever beam over the wall. The cantilever moment will be carried by the back span with zero moment on the wall. You will have some small moments due to rotation, but it will relieve itself.
RE: Steel Beam Over Concrete Column/Wall Connection
You may require a heavier base plate because many smaller beams have a relatively thin flange and you may require stiffeners at/near the face of the column to take the forces from your anchor rods to the column itself. Also have to check for interference with column reinforcing. For the small column you have there can be a great loss in moment resistance if you move the anchor rods an inch or so...
Dik
RE: Steel Beam Over Concrete Column/Wall Connection
So in essence the connection would only be to resist uplift loads?
I would not need to design my bolts in the case of the steel beam over the concrete column for tension resulting from the moment?
RE: Steel Beam Over Concrete Column/Wall Connection
RE: Steel Beam Over Concrete Column/Wall Connection
RE: Steel Beam Over Concrete Column/Wall Connection
A round bar normal to the beam on top of the baseplate would provide a hinged condition. A square bar is nearly as good. In either case, the beam requires stiffeners above the bar.
BA
RE: Steel Beam Over Concrete Column/Wall Connection
RE: Steel Beam Over Concrete Column/Wall Connection
RE: Steel Beam Over Concrete Column/Wall Connection
RE: Steel Beam Over Concrete Column/Wall Connection
RE: Steel Beam Over Concrete Column/Wall Connection
I went ahead and only used the bolts needed for uplift, and placed them more towards the center of the column. I assumed a pinned condition for design.
Please see attached sketch for another situation. I have a cantilever steel beam supported on a concrete wall, with no backspan. I am thinking of bolting a column to the side of the concrete wall as shown. I would really appreciate your comments. Thanks again.
RE: Steel Beam Over Concrete Column/Wall Connection
BA
RE: Steel Beam Over Concrete Column/Wall Connection
You could also use saddle plates instead of the column. You will have a plate on the front and back of the wall (each sized to take the force due to moment / wall thickness). You can then use the same threaded rod concept.
RE: Steel Beam Over Concrete Column/Wall Connection
RE: Steel Beam Over Concrete Column/Wall Connection
RE: Steel Beam Over Concrete Column/Wall Connection
Along with BA's concern, is this wall already built? Maybe you can provide a thickened section of wall (pilaster) in that area, or what about a steel column, where the wall is cast around it?
RE: Steel Beam Over Concrete Column/Wall Connection