Welded Splice

[KOTOR1]

I need to design a welded splice at beam to beam connection only taking gravity loads (cantilvered system). One of the beams was about 2" short. I cannot full pen the flanges as I had detailed. The owner does not want to see bolts at the splice and does not want to see the splice plate exposed.(The beams are storefront beams) Is it possible to have a single splice plate welded to the webs of the beam on the non exposed sides? . Has any one designed a welded splice in such fashion.

 

[nutte]

What was the shear splice supposed to look like before? A plate welded to one beam and bolted to the other? If so, design a longer plate so you can use the same bolt holes.

If it was bolted to both beams, you could do the same thing.

I would not recommend using a plate welded to both beams, since you would not have any mechanism to allow for rotation, providing the pinned support you designed the beam for.

 

[kslee1000]

"Luckily, the beams did work"

The beam "worked" - claim made through confirmation by calculation, or just field observation on the finished/modified product? Load capacity of the "Design" and "as Build" wouldn't be identical, would it (the change) causes long term problem? Please elaborate further.

 

[KOTOR1]

The cont. beam (with a point load at the newly formed cantilever) do work structurally after new calculations with original design loads.
The smaller beam also is structurally adequate.

 

[civilperson]

A 2" gap can easily be filled with weld material. Use web backing plate and fill the gap with weld. (Same as full length beam when completed).

 

[BAretired]

Another possibility, to get around the rotation argument raised by nutte is to use two vertical angles. The leg parallel to the webs would be welded. The other legs would be bolted together. Beam rotation would be permitted by slight bending of the bolted legs.

Best regards,

BA

 

[nutte]

If you're trying to achieve a pinned condition, I would not recommend civilperson's suggestion.

 

[kslee1000]

kotor1:

If strength of the beams are adequate, make sure the beam end rotation/deflection at the pin is acceptable. Also, is there any transverse brace to keep the beams stable, side awing could spell trouble.

 

[KOTOR1]

The deflection at end of the cantilever is about 0.09 in down(total load). The beams have angle braces attached to the web at 8'-0" o.c that connect to the roof joists.

 

[BAretired]

kslee1000,

A brace to the bottom flange at or near the connection would provide torsional restraint to both beams. We can't say whether or not it is necessary as we don't know the geometry of the structure.

An eccentric connection between the two beams does not produce torsion in either beam. If a double angle is used and the bolts are 2" from the center of each beam, there is a torsional moment (24x2=48k") to be resisted by the bolts, but no torsion in either beam.



Best regards,

BA

 

[kslee1000]

kotor1:

Seems you have very good grab of the whole event. Wish you best luck.