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EBAT75

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What is recommended method to calculate first order Delta and acceptable for the exam? 

 
Moderator, in case this post can be construed as transgressing NCEES exam integrity policy, please delete it. My intent was to see if anyone used a given method and achieved Acceptable on the problem as a whole. Nothing more.

 
By hand

Edit: Can you be a little more specific?  Do you have a particular material or lateral system in mind that you're asking about methods of calculating deflection for?  My answer was tongue in cheek because the question is a little vague...happy to give you my thoughts.  From what I've seen on the NCEES practice exam and the AEI class, it seems like a lot of the afternoon questions will be focused on loading and detailing requirements...I could see them asking for drift though I suppose

 
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EB, you are good.

I assume that you are talking about steel. Any method allowed by chapter C if the AISC is acceptable. It's as easy as that.

If you are a member if AISC, design guide #28 can definitely help and give you quite a bit of insight on this topic. If you are a member, you can download this for free. If not, you can buy it. 

But if you are simply looking at what is required for the exam, anything in chapter C is just fine.

 
Thank you daywalker and kevo.

Yes, by hand at the exam. I like the humor. i kept this general because stability analysis of both steel and concrete frames run on parallel tracks. Both involve using Delta. However, the examples I have seen give the deflection-delta value rather than calculate it. e.g. Seismic Manual - Moment Frame Ex. 2.4 Taken from software I think.

if I have to calculate it, I am thinking  of applied force divided by rigidity (calculated from stiffness parameters). At least for simpler moment frames. 
 

 
I think if the exam asks you to calculate it, it'll most likely tell you which method to use (for consistency in grading).

 

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