Quasi-static cyclic Analysis stops without any warning

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[email protected]
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Quasi-static cyclic Analysis stops without any warning

Post by [email protected] » Thu Oct 24, 2024 3:46 pm

Dear STKO team,

I'm working on validating a numerical model that simulates the cyclic response of RC rocking walls. I'm trying to simulate quasi-static cyclic test results available in the literature. However, when I tried to increase the number of analysis steps, the analysis stopped without any warning. While the number of analysis steps was larger, the analysis stopped earlier.

I wonder if there is an upper limit for the number of analysis steps.

I would appreciate it if you could help me with this.

I attached screenshots of the command line and monitor windows.

Thanks,

Franco
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Monitor.png
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kesavapraba
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Joined: Sat Mar 28, 2020 2:25 pm

Re: Quasi-static cyclic Analysis stops without any warning

Post by kesavapraba » Thu Oct 24, 2024 4:09 pm

Hi, without detailed information and also the model, It's difficult to provide you with solution. There could be many reasons.
:: With best wishes ::
Prabakaran Kesavan

[email protected]
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Re: Quasi-static cyclic Analysis stops without any warning

Post by [email protected] » Wed Nov 06, 2024 8:31 pm

Hi kesavapraba,

Thanks for replying. I don't know what information you need, the analysis ends without a warning or error (the last step converged with one iteration).

I would like to know if there is an upper limit for the number of analysis steps or recorded data. I ask this because when I check the .mpo database for different numbers of analysis steps after the analysis stops, the size is the same (see attached figure).

Thanks again.

Franco
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size of mpco files.png
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kesavapraba
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Re: Quasi-static cyclic Analysis stops without any warning

Post by kesavapraba » Thu Nov 07, 2024 5:17 am

Hi, Number of analysis steps do not make the analysis to stop. Also, it is not clear to me from your post the number of analysis steps that you used and the analysis settings (allgorithm, error norm etc.). Without such details, it is challenging to debug and suggest any solution. When you say that the model stops after a certain steps, the structure might have reached its failure point! If the model is available, one can atlleast check and try to provide the solution.
:: With best wishes ::
Prabakaran Kesavan

STKO Team
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Joined: Tue Oct 29, 2019 8:45 am

Re: Quasi-static cyclic Analysis stops without any warning

Post by STKO Team » Mon Nov 25, 2024 9:38 am

I don't know the details of your model but certainly there are some issues!
Looking at the output from opensees you can see that you accept a huge error! 1.0e11.
In this way, the results are garbage and the simulation can suddenly blow up.

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