topic Re: Reinforcement in Robot Structural Analysis Forum

Reinforcement

Nairi85 — Mon, 20 Apr 2015 13:29:37 GMT

Good day!

Please see why this turns unrealistically high reinforced concrete columns ???
Theoretical and actual reinforcement differ from each other dozens of times !!
Reinforcement do according to the norms of Europe, the version of the program RSA 2015 SP5.
Calculation file attached to the letter.
thanks in advance.

Re: Reinforcement

Nairi85 — Tue, 21 Apr 2015 05:31:39 GMT

Good day!
Artur really need your help, please see my model.

Re: Reinforcement

Artur.Kosakowski — Tue, 21 Apr 2015 08:21:07 GMT

Have you included seismic combinations in both RC modules?

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Re: Reinforcement

Nairi85 — Tue, 21 Apr 2015 10:58:49 GMT

Artur, I'm sorry, I forgot to tick a combination of ALS (

I'm ashamed of it. With this question decided, thank you very much.

Now help in issue that plagues almost a month. The fact is that in any case I get excessively high reinforcement. And can not seem to find the problem points. It's only a two-story building, and I get reinforcement for high-rise building. Therefore I will not be reinforced column, two-story building, 12 rebars F40 B500s ....
I beg you to help me to overcome these difficulties.

Re: Reinforcement

Artur.Kosakowski — Tue, 21 Apr 2015 11:32:41 GMT

As the high amount of reinforcement is apparently due to seismic loads I think you should start with checking the results for these cases first. Are the obtained values of forces as you would expect them to be or higher?

Re: Reinforcement

Nairi85 — Tue, 21 Apr 2015 13:57:40 GMT

Artur, I have more than a year studying the question of how to do seismic analysis according to the norms of the Republic of Armenia in the RSA.
As a result, study researches, I wrote an application with the help of which, I'm counting seismic spectra of our code.
Currently Armenian seismic code implemented in the computational program Lira Sapr. I managed to Contact as one of the developers of this program, and he explained to me how they have implemented our code in Lira.
Similarly, I have written an application for RSA. Results in advance to send experts from Lira, he confirmed that everything is done right.
Almost all of my colleagues, design calculations made in the calculation of the Lira, and exactly the same seismic conditions never get Results, I get into a RSA.
If the difference was small, I would not much worried on this score.
But unfortunately I get the result to many times (
Artur, I do not have your experience, and I'm probably alone can not identify the problem. And the fact is that throughout Armenia, but I'm trying to make friends with the Robot, and therefore no one to ask for advice. Application for the calculation of the spectra I attached to the letter.

Please help overcome this barrier

__________________

Артур я уже больше года изучаю вопрос, как сделать сейсмический расчет по нормам республики Армения в Роботе.
В результате иследований, я написал приложение, с помощи которого, расчитываю сейсмические спектры из нашего кода.
В настоящее время армянский сейсмический код реализован в расчетной программе Лира Сапр. Мне удалось связатся с одним из разработчиком этой программы, и он мне обяснил как они реализовали наш код в Лире.
Точно так же я написал приложение для Робота. Резултат заранее отправил специалисту из Лира Сапр, он подтвердил что все сделано верно.
Почти все мои коллеги, расчеты конструкции делают в лире, и точно в таких же сейсмических условиях никогда не получают резултаты, которые я получаю в Роботе.
Если бы разница была маленькая, я бы сильно не тревожился на этот счет.
Но к сожалению я получаю резултаты в много раз больше(
Артур, у меня нет вашего опыта, и наверное я самостоятельно не смогу выявить проблему. И дело в том что в всей Армении, только я пытаюсь подружится с Роботом, и по этому не у кого спросить совет. Приложение по расчету спектров я прикрепил к письму.

Прошу, помогите преодолеть эту преграду

Re: Reinforcement

Artur.Kosakowski — Wed, 22 Apr 2015 06:45:34 GMT

I'm sorry but I don't feel like my knowledge is good enough to tell if the definition of the response spectra you used in the model is right or wrong but it can be seen that comparing with the EC* seismic analysis with the default settings it produces significantly larger forces. I'm attaching the comparison of the spectra for these two situations:

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Re: Reinforcement

Nairi85 — Wed, 22 Apr 2015 12:40:32 GMT

Hi, Artur.
It seems the situation is slowly beginning to clear up.
Please tell me, when you compare our my spectrum with spectrum of EC8, what acceleration, and the type of foundation set in the settings EC8?
I have ag = 3 m/s2, the type of foundation on Eurocode =''C''.
Please supply these values, and attach the form of the spectrum for comparison with my spectrum.

Re: Reinforcement

Artur.Kosakowski — Thu, 23 Apr 2015 07:41:39 GMT

My point wasn't about your spectrum being wrong (I don't have enough knowledge to tell and on the contrary as you already compared it with other resources I would assume it is actually correct) but the fact that it produces large forces. You need to determine if they are right (and then increase sizes of columns) or seem to big. For the latter you may check if you shouldn't apply behaviour factor and e.g. divide the seismic forces by the corresponding factor. You may want to look at e.g. http://www.scielo.org.za/scielo.php?script=sci_arttext&pid=S1021-20192010000100003 (table 4) or look at the table for another source shown below:

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

Re: Reinforcement

Nairi85 — Sat, 25 Apr 2015 14:54:39 GMT

Hello, Artur. Thank you for the information.
Artur, I once again checked the calculations in my application, and inclined to think that I have done right, according to the code СНРА II-6.02-2006.
Armenian seismic code is very conservative, and I can not afford to change the points and thus commit themselves.
On the other hand, many of my colleagues who work in computing programs such as the Lira, MicroFe, Scad, never get such inflated results.
I want to understand why the Robot generates such large seismic forces!
To do this, I created a simple task to Results razed to the results obtained from the Lira and MicroFe.
Please see Results of reactions, although setting up a correctly spotted, the control value indicates that the calculation is not done properly.
Why is there such a situation and how to fix it ??

Re: Reinforcement

Artur.Kosakowski — Mon, 27 Apr 2015 07:14:30 GMT

Could you send this file please?

Re: Reinforcement

Nairi85 — Mon, 27 Apr 2015 10:29:30 GMT

Arthur good day.
File I attached in my last letter: http://joxi.ru/DrlagJ7cEoWomP
You do not show?

Re: Reinforcement

Artur.Kosakowski — Mon, 27 Apr 2015 10:40:09 GMT

I have some issue to download it from this site. As it is a small file attach it directly to your post on the Robot forum please. Thank you.

Re: Reinforcement

Nairi85 — Mon, 27 Apr 2015 11:14:02 GMT

Artur, please see this link: https://yadi.sk/d/krcrnlirgGgqG

Re: Reinforcement

Artur.Kosakowski — Mon, 27 Apr 2015 13:20:13 GMT

In the parameters of the modal case use either other method than Block Lanczos or set mass matrix as either lumped with rotations or consistent.

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Re: Reinforcement

Nairi85 — Mon, 27 Apr 2015 15:07:59 GMT

Thank you, Artur! Once again, convinced that without your help on this forum, it would be very difficult to overcome your difficulties ...
Please tell me how to get the symbols and values of seismic loads in the graphics window model ??

Re: Reinforcement

Artur.Kosakowski — Tue, 28 Apr 2015 07:49:43 GMT

Please tell me how to get the symbols and values of seismic loads in the graphics window model ??

I'm not sure if I understand you correctly. Could you make a screen capture that illustrates what kind of symbols and values you would like to see?

Re: Reinforcement

Nairi85 — Tue, 28 Apr 2015 11:09:54 GMT

Re: Reinforcement

Artur.Kosakowski — Tue, 28 Apr 2015 12:24:04 GMT

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

Re: Reinforcement

Nairi85 — Tue, 28 Apr 2015 12:32:23 GMT

Thank you, friend.