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thedaywa1ker

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About thedaywa1ker

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    Project Manager

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  • Engineering Field
    Structural
  • License
    PE
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    Structural

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  1. I walked out feeling pretty good. With every day that passes I feel less confident. I feel like I should already be studying for April. I've figured out where I went wrong on a few morning questions, but I still feel like I had a good showing in the afternoon. We'll see.
  2. I don't understand why you are feeding Lb=0 into F2-2 when (a) says that LTB doesn't apply when Lb<Lp. F2-2 only applies when Lp<Lb<Lr Regardless, the end of F2-2 says <=Mp, so if the equation does equal more than Mp, then you still use Mp. This is meant for the case of Cb > 1, because you shouldn't even be going down this rabbit hole if Lb=zero, per (a). I'm not sure what you're saying with the W16x100. The moment from the loads in table 3-6 equal Mp, like I've been saying. Am I missing something?
  3. Compatibility method. Analyze just the right half, assuming the hinge is a spring with stiffness of the left cantilever...find the reaction at the spring, use that to find the moment at the left end. I'll try to post an actual solution after work
  4. I just scrolled through some of those old results threads and found the posts you're talking about Present_SE. That guy has a way with words, and makes me feel less confident about my chances, seeing as I'm not nearly as confident as he and apparently many others were. But, those threads will give me some therapeutic reading in the even that I did fail again. Misery loves company.
  5. Yes there will be LTB if Lb>Lp, but then you can't use table 3-6 anymore, because the table values assume Lb<Lp. If you are looking at table 3-6, then yes, the moments from those loads equal Mp (unless it is above the bold line where shear controls)
  6. Page 3-9 of the steel manual...immediately prior to tables 3-6 and 3-10... I don't see anything in what you've posted that would lead me to believe that the writers of that code mean anything by Lb other than what they have explicitly defined. The question of specifically what kind of restraint is sufficient in real life to prevent LTB is a can of worms. But, AISC simplifies it for us dumb designers with their definition of Lb, so that we can do a quick check and move on
  7. There was a guy that showed up to the SC testing location on the 2nd day ready to take his Vertical exam. I'm pretty sure I had a dream that that happened to me. What a nightmare.
  8. It is on page 3-9 I am most curious for your answer to this post:
  9. Are you saying that you back-calculate phi*Mpx from 3-6, to then use with equation 3-4a?
  10. Looking at the capacities in 3-6 Say you have a beam spanning 40 feet. You are saying that you can use this table for unbraced lengths up to Lr. How do you tell the table what your unbraced length is? A particular beam that spans 40 feet only has one capacity per table 3-6. As the beams laterally unbraced length increases, the capacity will decrease. How is this reflected in that table? It isnt.
  11. F2-3 has the definition of Lb that I am familiar with. I am asking why you think that the definition of Lb changes, and where that is in the code. Your changing definition of Lb is why your interpretations of 3-10 and 3-6 are off. 3-6 assumes Lb of zero (for all intents and purposes), aka fully laterally braced. Lb/Lr/Lp aren't relevant to that table at all. I don't think these statements are correct.
  12. I took both. I felt that the difficulty was pretty much in line with what I expected. I felt 'prepared', but its a hell of a test, so I don't know that anyone will ever feel like they knocked it out of the park. I felt confident in right at 70% of the morning portions of both , and felt pretty good about the afternoons...but since there is no way to know if I'm totally screwing up the afternoons, who knows. I feel like if I get a grader in a good mood for the afternoons I'll have a shot at passing both. Fingers crossed.
  13. I remember what you said earlier, I just don't think that is true. Can you give me a code reference for this alternate definition of Lb? 'Up to Lr, fully braced' I am confused. If a beam is unbraced up to Lr, then it is not fully braced.
  14. Well this topic aged well. Im so grateful for this class. Worth every penny
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