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NCEES Problem 604 for SE Gravity

Wood

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#1 McEngr

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Posted 02 April 2012 - 01:52 PM

Part b of this problem is awful in my opinion... particularly the way they demonstrate that the tension-in-tension glulam controls. A better way to write the problem is to ask the examinee to orient the beam in the proper position, then design it for flexure+axial load. The funny part of this problem is that the compression-in-tension will never happen in the new scenario unless there is uplift. For the uplift scenario, the examinee could assume the beam to act independently of the truss system for quick conservatism at 0.6D+W.

My question is, why do they even check for the compression zone in tension scenario. By inspection, it's easy to see it doesn't happen. A good problem for compression zone in tension on a glulam is to do a mult-span glulam where he negative moment near the support would be in tension and you would ask the examinee which way to orient the beam for economy.

I suppose I'll digress... the pressure is getting closer and closer.

BTW~ has anyone received their exam instruction letter?

#2 Rhoadies

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Posted 07 April 2012 - 06:09 PM

I have had the same type of question for the Lateral afternoon problem 801. They ask for the design loads, when I designed the wall it was obvious that the controlling wind load on the parapet was the load from the windward side, so I did not calculate the leeward as it obviously did not control. However, the answer in the back calculated both sides. Maybe it's just a case of trying to show for our benefit how to do something? I don't know. I've talked with a friend who passed the SE last April and he suggested not to get caught up in that too much. The afternoon is where we get to prove that we do this for a living and we can do things such as "by inspection" and whatnot to shave some time.

As for the test admittance instructions I got an email on Monday or Tuesday with mine, I made three copies, one for my glove box, one with my mountain of references, and one for me to take on my person and try not to forget. I want a lot of redundancy with something this important.

What are people taking their references to the test in? My wife has a collapsible hand truck that I just realized today cannot fit all of my references. I'm intrigued to see what others are using.

#3 dakota_79

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Posted 09 April 2012 - 03:13 AM

I don't read it that they're checking compression zone in tension. They're checking compression zone in compression, and saying since the reference strength value is lower than the tension side reference strength value, compression side controls (in positive moment).

Either the way NCEES does it is wrong, or the way NDS lists their reference design values is misleading/incorrect.

#4 dakota_79

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Posted 09 April 2012 - 03:19 AM

Rhodies: be careful with leaving a copy in with your ref material, since you're not supposed to have any "loose" papers. Don't want to risk them thinking the wrong thing. I'd imagine they'd just take it from you if found, but personally I wouldn't risk having a loose sheet buried in with the books.

For transport, I'm using a rolling suitcase. Did the full-on simulated practice exam this weekend, and was pleased to find all of the ref material fit in it perfectly, and in a manner that will make it really easy to set up as a bookcase for quick check-out/put-back during the exam.

#5 dakota_79

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Posted 09 April 2012 - 03:24 AM

Also Rhoadies: I agree re: the afternoon stuff. Demonstrate a sound design, and demonstrate sound judgement in getting to that design, and you're gold. That has to be the way it is, since that's the point of this madness. If not, we're all screwed.

#6 kevo_55

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Posted 09 April 2012 - 11:56 AM

Demonstrate a sound design, and demonstrate sound judgement in getting to that design, and you're gold.


:appl:

You are 100% right.

That is all what this exam really is.





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