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I wouldn't think about it that way. The applied stress, fb, is 3x lower than it would be if you had one 2x10. The allowable stress is the same as if you had one 2x10. In other words: 1. Compute fb = M / S, where S is 3x the S for one 2x10. 2. Compute Fb' for one 2x10. 3. The triple 2x10 is...

Right. Current curricula might be a small part of it, but I'd bet the test is the explanation. When I took the old Strl I and Strl II in the early 2000s, the Strl II was a crapshoot. They would ask seismic questions that required that you had used that exact seismic force resisting system...

Part of the answer might be that BS programs allow fewer electives now than in years past, so BS grads have had very little structural coursework. 30 years ago, when I finished my BS, I had taken structural analysis, reinforced concrete, prestressed concrete, wood, matrix structural analysis...

That would be a gigantic shift, considering how many more PEs there are than SEs. It's pretty hard to believe they'd try that.

From what you've provided, it's hard to say, but the approach doesn't look correct at face value. If you're doing this in SAP2000, then the following is what you need to do: 1. Compute the slab transformed MOI for bending parallel to the ribs. It should be in units such as in.^4/ft or mm^4/m...

This is critical information. From what I've read, the common approach of two equal thickness nuts doesn't help.

I don't understand what you've typed. My best guess is you're trying to use SAP2000 to enhance or replace the calcs from the AISC Specification Section E3. SAP2000's linear eigenvalue analysis should give you the elastic buckling stress. That's equivalent to Fe in Section E3, not Fcr like...

On a previous project, welded connections caused major problems because of this. We got very far into the process, and some connections were already welded in place. THEN, someone upstream realized the steel is a few decades old and had uncertain material properties. They started naming the...

Some context would be good. Are you generating these for submittal and approval, or just for you?

In a moment connection, the shear connection can be designed for zero eccentricity. From the 16th ed. AISC Manual Page 11-4: "Shear is transferred through the beam-web shear connection. Since, by definition, the angle between the beam and column in an FR moment connection remains unchanged...

Once20036, we are all human, so it's understandable to save myself time at the expense of someone that I don't know down the chain. In this case, the balance is pretty bad, so it causes the indigestion. In the interest of being totally honest, the UDL approach is not a problem IF there is a...

Once20036, have you done any delegated design of connections? I've used EngDM's method before. Very often it works, but I have had the EOR come back and reject what was done, causing (unpaid) rework under very tight time constraints. Even when it works, I wasted time adding all of those "EOR...

You've given a pretty good example of why this approach is problematic. The LRFD reaction would be 40.25 kips. Chances are, the typical connection on the project is a shear tab. Only two bolts will fit in the W8. A shear tab with two 3/4 in. A325-N bolts is worth about 25 kips, so an atypical...

Once20036, there's a reason why this subject gets under people's skin. The energy for the rough comments comes from dealing with the consequences downstream. I'll give an example. In one of my first projects, the structural drawings said to design connections for 50% of the UDL. There were...

For the option of providing a slip connection, I thought the idea would be to resist Fp at the non-slip end. Is that not the case?

I had a couple of his steel classes also. His teaching style was 99th percentile. Old school writing on the chalk board before all of the modern bullcrap teaching methods came about. He built big labs at Oklahoma and at VT. The one at VT is awesome and it is named after him now...

Checking shop drawings is a repetitive and miserable task. Unfortunately, among that sea of correct items, there are errors. Maybe big errors. Some people have more tolerance for these types of tasks. Maybe that's not you. LOL. It's not me, either, BTW. If I found myself stuck doing that long...

I assume the angles are in tension. Could you weld a plate in between them to make them like a WT at the connection? I don't see an obvious way to compute U otherwise.

Salmon and Johnson, or the newer Salmon, Johnson, and Malhas has a great chapter on torsion. It's a lot easier to follow than what you'd find in an Advanced Mechanics of Materials or similar textbook. You might check that out. I started to point you to the AISC Design Guide 9, but it's so...

I don't understand the node in the middle. Is it just in the air, not connected to the rest of your plate? Are you trying to fill in the hole? For the node near the top-right, why not just move the closest adjacent node to that location? If that's a no-go, then I would delete the shell...