New HSS bracing for existing steel frame

[Heldbaum]

Hello folks, I am working on shop drawings for a steel contractor. Connections not specified in construction documents are delegated on the contractor as well. It is a vertical and horizontal extension of an existing steel bldg. EOR wants to brace one bay at two floors with HSS bracing - please see attached two screen-shot. This is an existing steel frame and white lines show where new HSS bracing will go. The problem is that the existing spandrel beams are not aligined with the columns, they are attached to the column flange, on the inside side of the column (very popular back in the days) with an angle and rivets. How would you "solve" that joint in this case where the column and the beam is not eccentric. Help will be much appreciated. Thank you in advance.

 

[r13]

Issue a RFI. The EOR might have missed detail of this special connection from the existing drawing.

 

[Heldbaum]

I am pretty sure he is aware of the setup. I would like to propose something for his review to save time

 

[r13]

Unless present in writing, the certainty is false. I wouldn't do anything, as it could be waste of time, either way (connect to beam or column) posses some problem. If you have full familiarity with the existing structure and the new design, then that's another story. You can post the intend solution for comments.

 

[Heldbaum]

Yes I will, thanks

 

[XR250]

That seems like something the EOR should design. I would never consider delegating an issue like that.

 

[KootK]

Has the EOR specified in which plane they want the bracing here? Will it be in the plane of the beams, the columns, or someplace else? You'd need this information at a minimum, otherwise you've no way to know / guess how the engineer intends for the eccentricity to be resolved.

 

[KootK]

Never mind. Looking closer at the drawings, the braces are concentric with the beams. I'll dream up something...

 

[KootK]

1) We're talking about pretty small loads here and;

2) You don't feel that the original connection could work as is.

This might be one of those cases where it would be advantageous to move the work point out into the beam span a bit.

I'm assuming that:

 

[Heldbaum]

KootK, thank you. This is something similar to what I've had in mind but did not think about that stiffener serving as a guesset plate... Anyways, I already sent an RFI to EOR to advise. Thanks a lot for your help and time and I Will post the final result.