Moment frame connection

[JStructsteel]

Got beam attaching to an existing column and needs to be a moment connection. They didnt pre-drill holes for future, so going will welded.

My first thought is a angle for setting the beam welded to existing, and they set the beam and bolt for temporarily. Come back and weld angle to new beam, top plate existing flange to new flange, and then any other plates needed, along with stiffeners.

Are there some good "standards" out there for this? I figuire design guide 39 for all the stiffener checks, flange, and web etc. Then just weld design for the top and bottom flanges.

 

[jhnblgr]

Why not template and mag drill the holes

 

[phamENG]

I agree - mag drilling is usually perfectly acceptable and, depending on the size and age of the column, is often less expensive than field welding with it's associated inspections and risks in existing buildings. Now if you have a 1" thick flange, mag drilling may not work so well. Though if you're already welding stiffeners to the existing, it may not matter too much.

I've never seen a standard for it. Just adapting to the condition.

 

[JStructsteel]

The columns are W18x76, Beams W27x94. Gonna be alot of drilling.

I can ask the contractor the question.

 

[DrZoidberWoop]

Would something like this work? Not sure what type of site constraints you have or how big of a moment the conx needs to resist, but you have a lot of options, including end plates, flange plates, direct welding, super glue, etc...