CANTILEVER STEEL BEAM TO CONCRETE WALL

[NAFTALI-HAKOHEN]

Hi all

Looking to cantilever some steel beams from a concrete wall, to support a walkway or bridge between two structures.

No columns are allowed under the bridge, and cantilevers are red in model/plans attached are and around 3m, or 1.5 meters.

The design concept is the simplest i could vision, just little unsure about the behaviour of some elements, due to the 3m length of the cantilever and large live loads (0.5t/m2)

The bridge itself is UPN 320 beams, with the UPN beam adjacent to building bolted to building along building length.

I dont have so much field/long term experience in how these embedded plates to a concrete wall behave, is it reliable, and the welding of the beam to the plate i assume is tricky.

Appreciate your thoughts, or ideas for more stable/less statically determinate proposal.

Thanks

N

 

[HS_PA_PE]

Are you allowed to use knee braces to support from below, or diagonal cables going up above?

 

[SWComposites]

how exactly is the concrete wall built? reinforced?

 

[Harbringer80]

This doesn't seem like a great idea but if you want to proceed you need to follow the load path. Check the wall for the existing loads plus the new additional out of plane moment, check top of wall connections for the out of plane loading, design plate to wall connections and of course design the beams.

I'd consider adding more cantilever beams to spread the load to out to more of the concrete wall.

 

[mikek396]

Looking at your plan view, it seems like a better load path would be to cantilever the blue beam at the left side to support the red tubes in the other direction at the top of the drawing

 

[JAE]

Another option might be to embed a vertical steel column in the concrete wall - flange flush with the face of concrete - and have a steel-to-steel moment connection for your cantilevers. This avoids the awkward bolting or embedded plates to a concrete wall that may be difficult.

This adds stiffness to the concrete wall where it needs it and possibly avoids nasty cracking due to the discreet moment applied at a singular point on the wall.