Beam to Column Web Moment Connection

[sbouvia]

I have attached a sketch of my question. I have received and inspection report that notes that the stiffeners added to the column web to transfer the moment into the column apparently were installed in the wrong position and therefore do not exactly line up with the beam flanges. I have a couple of questions, one is how can the full penetration weld still pass with this fit-up, and two is there any allowable fit-up difference as shown, when I look at the AWS code it allows fit-up difference in the dimension between the plates but not horizontal fit-up. See attached image.

 

[qcrobert]

I am unclear on exactly what you are asking but I have never seen a fit-up like the one presented in the attached sketch.

 

[connectegr]

Although AWS has fit-up tolerances, it is not intended to address whether the available weld is adequate. As shown you are losing a significant amount of the flange cross-section. I typically recommend increasing the web moment stiffener plate thickness by 1/4"-3/8" to account for miss-alignment (as shown), mill tolerances, and flange tilt. The moment capacity as shown is reduced to the cross sectional area of the weld, (Area x Fy x (0.6 or 0.9) x beam depth). The stiffener should be A572-50 to match the beam flange, or this will be an additional decrease in strength. Is the reduced capacity adequate for the load?

http://www.FerrellEngineering.com

 

[connectegr]

I did not answer your specific question. The CJP weld passes, but for a less effective depth. The inspector should question whether the effective weld depth is adequate for the intended condition. The weld can UT and show no defects, but the actual depth of weld is less than intended. This should be noted in the report as a non-conformance. The inspector should note when the effective weld depth of a CJP is less than the thickness of the thinner part.

http://www.FerrellEngineering.com

 

[sbouvia]

Thanks for your help, and the inspector did note the change in effective depth of the weld.