It is closed as far as: I can't bring in any reference material.
I couldn't imagine sitting there and flipping through some (unmarked) pdf (or whatever) to find what I need.
I remember that! The funny thing about that was (around that time): the gears switched on that. (IIRC around 2002-2004.) All the sudden the SE I & II pass rates switched. I.e. prior to that point, the SE I had high pass rate and the SE II had a low one. But that switched right around the time...
I guess that is possible....but when I was going through the SE I & II, I had a BS & MS (under the "old" system), and I had a hard time passing the SE I. In fact, the pass rates then are comparable to what they are now. So I don't know that I buy the education theory.
If they gave me a closed...
I agree.....but I have to question those pass rates. Why are they so much lower than other disciplines? Either one of two things are going on: the colleges are turning out lousy engineers in our discipline, or there is a issue with the test. I don't buy the former, I think it is the latter. It...
I didn't sift through all the replies (so someone may have already said this).....but this caught my eye. You are in the wrong code for shells. AISC is not meant to address them.
The safety factors for shell buckling can get very high (on the order of 10 to 20+) since initial imperfections can...
Well technically, they won't be licensed until they get the experience (even if they pass the exam immediately after college).
But practically speaking, (if we are talking the SE exam) I'd be surprised if anyone would pass that thing right out of school or just with a few years experience...
Measure, as in the field? I have a device (made by LANDTEK) that is pretty good at measuring vibrations (as long as the forcing frequency is 10 Hz or more). The info it is going to get is kind of limited (without more equipment). If i need a lot of (highly detailed) info.....I'll hire a third party.
Anytime. Btw, something I forgot to mention: check the web carefully for this load transfer (to the shear angles acting as a seat in this direction). Sometimes the web can severely limit the amount of load that can be transferred.
I've typically used the moment connection to transfer both strong & weak axis moments to the columns. It's just a matter of proportioning the utilization(s) for each case. (I.e. you used up X % of the capacity for the strong axis and Y% for the weak axis. Just make sure X+Y<100%.) The procedures...
Depends on the equipment.....and also the number of times it ramps up & down during it's use. I was brought it on one project (this is a specialty area of mine) where the equipment was having maintenance issues because of trasient motion that was not checked. This thing started up & ramped down...
There is a very real possibility that you will pass through a resonance frequency (for either the equipment or the supporting structure) during start up. (Note I say "a" resonance.....since there are multiple frequencies involved for such a system.) I normally check the displacements with a...
It is hard to say without knowing more than I know now. It would certainly stiffen things up (locally)- where you do have stiffeners.
In a vibration problem, you are looking for a landmine....only calculations tell you where that is. (I.e. stiffening things could actually make the vibration...
Do you have 'Roark's Formulas for Stress and Strain'? He has a lot of formulas for it.
If we are talking about a circular cross section, the formula is:
Φ=TL/JG
Where:
Φ= rotation [in radians]
T=applied torque
L=Length
J=Polar moment of inertia
G=Shear modulus
Agree with centondollar: web stiffeners will not change the torsional stiffness of the beam. I did a FEA study on this some years back.....and you have to add a impractical number of them to make a difference. I like the brace idea others have proposed.
For a electric motor (at least the kind I am use to dealing with) there would be both vertical and horizontal unbalanced force (one of them having a different phase angle than the other). Of course, we don't know what the machine actually is.
Thanks Heaviside. Good info
And to answer a question that has come up.....I have no idea what a "AHJ" is. This is a private farm in South Carolina (if that helps).
The thing about it is: it appears to have been well maintained. (Fresh paint and all.) You wouldn't know (unless you ran numbers on it) what the real issue was.
If it does collapse.....I doubt he will mention to the insurance guy the fact I warned him. [smile]