Web Access Holes Required for Low Moment, Statically Loaded Connections

[vStevev]

Hi All,

Does anyone have any advice on whether web access holes are mandatory in situations where CJP and fatigue analysis are not required? The issue I'm having, is that our beam coping machine is unable to cut-out the web underneath the flange. So the detail ends up looking like this:

My understanding is the web access hole helps facilitate a sound weld in the flange-web region, and helps with cooling. But if the connection is loaded to say 20% of the moment capacity, and a PJP is sufficient - is this style of cope acceptable?

Thanks!

 

[gtaw]

If you have no code restrictions and no engineering concerns - no problem. If a partial joint penetration is all that is necessary and if there is sufficient area to place the weld of the proper size to transfer the load, and it the loads are static, I see no problem.

Would I rather see a proper access hole and would I rather see a CJP? Sure, but it is unnecessary it increases cost without an additional value. Would I like my car radiator fabricated out of gold for better heat transfer. Sure I would, but there is no cost benefit of having a gold radiator unless I take into consideration the scrap value.

Best regards - Al

 

[vStevev]

Thanks for the reply. I agree completely with your logic that if it's unnecessary by design, why add it... Where it's been confusing is whether web access holes, when used, must follow the details exactly as set forth by both CSA W59 and AWS D1.1. See image below:

It seems the perception for some is that yes, if a rat hole is used then l > 1.5tw is a code requirement. But my thought is that this should only be required for a CJP where NDE defects are unacceptable. Why go to this extreme for basic skid design, where deflection control is paramount and connection moments are low?

Unfortunately, neither code elaborates much on these details, and there has hence been confusion on the scope of their intent.

 

[gtaw]

The original post did not say D1.1 or CSA W59 applied, but in any case, the details shown are to accommodate CJP and where needed, a backing bar.

Consider if you will a simple framed connection where the top and bottom flanges are not welded. The copes in those cases do not utilize the access hole details shown in your figures. They are unnecessary.

If CJP groove welds are unnecessary, if sufficient access is provided to weld from one side, where PJP does not necessitate the need for a backing bar, there is no justification for the access hole.

Best regards - Al