The following picture is pretty self-explanatory. I need a connection for a beam that is coming in very close to a concrete wall edge (north/south beam in picture). The embedded plate with nelson studs in already in place. I was thinking a T type welded plate with bolts already fixed to plate (as drawn in purple), but they wont be able to weld both sides of the plate. Maybe with a full penetration backed weld? Any better ideas on how to fix this beam? Required shear for full beam capacity is about 175 kN and factored load is about 50 kN to give a quick idea.
$\begingroup$
$\endgroup$
Add a comment
|
1 Answer
$\begingroup$
$\endgroup$
2
Full penetration weld would be ok. I am more concerned about that bolts between the beam and the concrete edge. It could be difficult to tight them and inspection would be problematic too. Also you loose a considerable part of the flanges, at the beam edge, and therefore you cause a severe drop of the moment strength. I don't know if this is acceptable for your design.
A more simple solution i came up, is shown in the figure below. The beam is cut a little shorter in order to be flush with the concrete face and thus avoid flange trimming. A plate (pink color) is fastened with fillet welds at the anchor plate. A filler plate (green) is used to fill the space between the pink plate and the beam web. With this design, access for inspection and repairs remains good. No installation problems too.
Another advantage from placing the pink plate parallel to the edge, is that no bending is transferred to it. As a result, you avoid any additional bending of the anchor plate, tension of the anchors and compression stresses on the concrete. But you may induce more shear to the anchors (not certain if it is worst, because shear is induced by your design too).
What verifications are needed:
- Fillet Welds of the pink plate
- Anchors due to the additional shear (there will be a torsional component)
- Bolts (considering the filler plate)
- Pink plate in bending/shear
- Beam web
-
$\begingroup$ I had thought about this for a while, but I had in mind only using one thick plate (green and pink combined). Any reason why you opt for two thinner plates? I had brought the beam closer to minimize torsion to the plate and and studs, but I agree with you it will be much simpler this way and recalculating is worth it. $\endgroup$ Commented Jan 23, 2017 at 21:53
-
$\begingroup$ two plates may be necessary if the distance up to the beam web is bigger than the available plates on market. If that's not the case, one plate is of course simpler/better. $\endgroup$ Commented Jan 23, 2017 at 23:16