Hybrid steel beam moment connection

[haynewp]

I have a request to use a bolted (pre-tensioned) moment connection for the top flange of a steel beam with a CJP weld at the bottom flange. This is for a splice in an underhung crane that will seldomly be used. The shear plate at the web appears to also require welds based on the crane wheel assembly clearances as the rolling assembly could hit bolts in the web.

I have never used a moment connection that had a bolted flange plate at one flange and welds at the other flange. I have decided I am going to recommend against it since this is only to save in some field welding they didn't want to do and I'm not comfortable doing this. But I am interested if there is anything outside of AISC J1.8 that I can point to that discourages a hybrid connection like this or if anyone else has done it. I can't find any moment connections in AISC that show this type of arrangement either.

 

[Teguci]

AISC 14th Edition - J1.8 - "Bolts shall not be considered as sharing the load in combination with welds, ..." - apparently this is quite the departure from previous versions. I'm not sure why we are still entertaining this as a real response. Did this get revised in later versions?

Even if we were to take the liberal position that the load can be divided into separate Tension and Compression loads, you still need to deal with the sharing of the compression load which would get us back to J1.8.

http://www.jflf.org/v/vspfiles/assets/pdf/design_file202.pdf

 

[canwesteng]

Hate the connection too - just chiming in for a possible solution, how about you install a hanger at this location and don't splice it at all?

 

[haynewp]

I’ve already sent my recommendation with welds at the top and btm flanges. I will keep a hanger in mind if there is more pushback.