UBC 1997 vs ASCE 2010 Eaethquake

[drasticxxxx]

Hello,
Actually I am based on Dubai and working there, and we are using the UBC 97 as approved by municipality, however I was curios to read about ASCE 2010 ,just to see the differences and what I found that ASCE is more detailed and more comprehensive reference than UBC 97, and it is really the same as IB2009(I figure this with quick skim in IBC2009).

Actually I have couple of questions that I would like to ask
1. In ASCE 12.14 closure is not clear, so anyone can explain it more
2. I can’t understand the definition of grade plane in chapter 11 in ASCE
3. Non parallel system irregularity is totally not clear for both UBC and ASCE
4. I found in ASCE that drift is calculated in the center of mass between the upper and bottom levels, but if seen my colleagues in work in UBC 1997 using the average drift, so does both codes differ or I can use average
5. In ASCE 12.9.4.2, a member in this community which I do really respect, told me before, that you don’t need to make scaling when checking drift, but actually 12.9.4.2, ask us to do scaling, so I am wondering if there is something missing in my understanding
6. Based on ASCE, if I want to pick seismic design category, there is two tables based on S1, Ss, so shall I pick the critical category
7. Finally In Dubai they are designing based on 2B ZONE (UBC 1997)(however UBC 1997 SAY 0 but this decision is municipality decision) , so I wonder which S1,SS will give similar results to 2b zone??Any reference
Thank you all guys

 

[drasticxxxx]

I know that they are couple of brilliant minds in this community ,so please let us share knowledge

 

[wannabeSE]

1. I never use the "simplified method, so I don't understand the question. What "closure"?
2. What don't you understand about the definition of Grade Plane? Does figure C11-1 in the commentary need clarification?
3. Non-parallel systems occur when some of the frames/ lateral elements are not all parallel or orthogonal. For instance, when one or more frames are skewed 45° in plan from others.
4. I don't remember the UBC requirements off the top of my head.
5. Scaling drift is new in the 2010 edition. But, it is only when the base shear is less than 0.85 of the base shear calculated with equation 12.8-6 where C_s = 0.5 S₁ / (R/I_e). So, it may not govern many cases.
6. Mostly yes, but read the text of section 11.6 for other requirements.
7. I can't help you with this. Maybe use some algebra to find a solution. Or, look up the S1 and Ss in UFC 3 310 01,

https://www.wbdg.org/ccb/DOD/UFC/ARCHIVES/ufc_3_310_01_c2.pdf

 

[drasticxxxx]

Thank you for your response
1.Sorry, I meant 12.1.4 , not the simplified method
2.Actually I cant understand it ,what is the 6 ft and what is 12 ft(language complicated)
3.you said what the code is saying,but i need to see picture of one case to understand it
4. UBC requirement doesn't mention that drift should be the in the center of mass but ASCE mention this,so that why i have confusion
5.now I understand ,it is new this the reason,but why Cs is multiplied by 0.5(not like the code)??
6.Clear
7.I search in the link but ,cant find UAE, but I think as you said ,model with manual calculation could give me a hint, I will give it a try

Thanks again