I don't know what I was thinking yesterday. As others have pointed out, under just the gravity load, even with the inclined interface, the load to the purlin is only vertical - thus bending about the strong axis only.
However, under wind load, now you have bi-axial bending.
I see what you're saying, but when I read it, it sounds like they are just giving the case of the rotated purlin as one example of "many" possible cases where the member is loaded obliquely. But I'm just looking at the section you provided.
I don't think so. Considering the free body diagrams, it would be like a mass on an inclined plane. The reaction is normal to the plane of the interface, which results in loading about the strong and weak axis.
That's my take.
Just a thought, you could explore plug welding the decking from above to the HSS. If that could be made to work, the seams wouldn't have to land on the beams, as is the case for the fillet welding solution suggested by @HTURKAK above.
Regarding the "non-compressibility", my thought would be achieving the bolt tensioning values/ clamping force, while maintaining dimensions, would be complicated by including a ply with low compressive stiffness.
KootK, regarding your point 2), in many cases wouldn't the section just beyond the end of the bolt pattern would have the greatest concentration of stress (minimal spread and no longer strengthened by the connected member)? I suppose there could be cases with strange geometry that would violate...
I'd dig into some of the AISC journals. I believe Prof. Bo Dowswell at UAB has written some papers on applying the Whitmore section in different scenarios, so that might be someone to ask.
I would consider taking the width to be that of the bolt row, but that wouldn't be very economical.
Structural is a different branch of engineering. Maybe consider getting someone who knows structural design to design the structure...
have you considered seismic loads?
Could the reviewer have meant "max shear stress theory" (Tresca stress)? Tresca is always more conservative than Von Mises. Here's a rough diagram showing the different theories.
Your assumption is correct, that in the first case the columns are taking shear and bending. Consider the node on the right of the third story: it has no means of reacting the horizontal load imparted by the beam except by shear in the column. That's likely why the method of sections isn't...
Apologies for the delayed reply.
1.) "Figured as much, I should design each to handle 100% load then?"
Yes I think so, and that seems to be what others in the thread are suggesting.
2.) "How does the load path get more complicated with the gussets? I figured it was creating a smoother path for...
Just some quick thoughts:
1.) accounting for combined strength of weld and bolts is difficult- figuring how much stress goes where/strain compatibility. In the AISC 360-2015 spec, it's not allowed except in the design of shear connections on a common faying surface with strain compatibility...
Sosipater, it's working pretty well. I've just started using this setup so it's taking some time to get used to the drawing tablet, but I'm finding it faster than scanning in sketches on paper. Also being able to type notes on the side of the sketch is nice. I'm sure there's better software out...
