Field Fabricated Ordinary Moment Frame (Construction Mistake)
Field Fabricated Ordinary Moment Frame (Construction Mistake)
(OP)
All,
I am looking for some opinions on field made - post installation moment frames. I have project, where the contract drawings and shop drawings all clearly illustrated a moment frame along a line of a small commercial addition. The steel arrived and was installed and then framing went up. One weekend i drove by and looked at the project (prior to Special inspections call) and noticed the steel in place was not prepped or cut to be a moment frames and the flanges were not welded... I am going to kick this back at the fabricator since the product delivered was not what was specified but we have a good relation with the contractor which means we will probably be the ones detailing a repair down the road.
1) Can the proper beam modifications be made in the field (ie flange bezels and web treatments) in your experience?
2) Most cost effective way to fix, construction wise?
Notes: columns are HSS, beams are W16x26, Ordinary moment frames only resisting wind forces. There are 3 consecutive frames (3 beams, 4 columns, 6 connections) The HSS walls were designed to handle the flange couples and shear.
I am looking for some opinions on field made - post installation moment frames. I have project, where the contract drawings and shop drawings all clearly illustrated a moment frame along a line of a small commercial addition. The steel arrived and was installed and then framing went up. One weekend i drove by and looked at the project (prior to Special inspections call) and noticed the steel in place was not prepped or cut to be a moment frames and the flanges were not welded... I am going to kick this back at the fabricator since the product delivered was not what was specified but we have a good relation with the contractor which means we will probably be the ones detailing a repair down the road.
1) Can the proper beam modifications be made in the field (ie flange bezels and web treatments) in your experience?
2) Most cost effective way to fix, construction wise?
Notes: columns are HSS, beams are W16x26, Ordinary moment frames only resisting wind forces. There are 3 consecutive frames (3 beams, 4 columns, 6 connections) The HSS walls were designed to handle the flange couples and shear.






RE: Field Fabricated Ordinary Moment Frame (Construction Mistake)
If the shops showed a moment frame and nothing was fabricated that way I wold be concerned what else is missing/not right
RE: Field Fabricated Ordinary Moment Frame (Construction Mistake)
Thanks for the input.
RE: Field Fabricated Ordinary Moment Frame (Construction Mistake)
Adding bevels in the field may prove to be a problem as there are certain requirements for the root opening of a CJP weld in AWS. As currently fabricated you are probably 1/2" away from the face of the column to the edge of the flange as it is now. You would also probably need to cut a "rat hole" (which is probably a requirement of a OMF anyway) in the web so they can properly do the weld.
Adding flange plates top and bottom may be a better alternative but I'm not up on my OMF requirements so I don't know if they are allowed or not.
RE: Field Fabricated Ordinary Moment Frame (Construction Mistake)
RE: Field Fabricated Ordinary Moment Frame (Construction Mistake)
Thanks
RE: Field Fabricated Ordinary Moment Frame (Construction Mistake)
I'm all for helping the guys out.... but if your plans show a moment frame and the shop drawings show a moment frame and one isn't there I would be breathing fire on everyone around. Why should you have to come up with the fix, you should put the fix on the fabricator to hire and engineer to perform the necessary engineering and for you to review their design. You can be certain if you made the mistake they would be sticking this back on the owner with a hefty markup.
RE: Field Fabricated Ordinary Moment Frame (Construction Mistake)
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RE: Field Fabricated Ordinary Moment Frame (Construction Mistake)
We kicked it back to the fabricator and they of course say "Not our issue" which is a load of usual. The GC does a lot of work with us and has hired us to come up with a fix and they will back charge the fabricator or withhold payment.
The proper moment frame prep cannot be completed within any degree of cleanliness so really I think I am not going to even try. I will be welding plates to flanges, then connecting those to the columns. I will be making the moment-couple symmetrical about the column axis. So Flange plates it is, just not your typical Flange Plates. Luckily the columns have excessive attachment capacities than applied moments.
RE: Field Fabricated Ordinary Moment Frame (Construction Mistake)