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Re: SFI-MVLEM modelling

Posted: Mon Sep 30, 2024 4:23 am
by BrownTrout_NZ
Hi STKO team

I still got some issues with convergency for both push over static and time history. For the static push over case, it was working fine when I had only single Storey walls but when I developed into multi-Storey structure, static does not converge (stop @ around 47% in). Could someone in STKO please have a look at the attached files and make some recommendations in relating to how to handle the convergency issues. Your input will be much appreciated.

Capture error mesage.PNG
Capture error mesage.PNG (58.95 KiB) Viewed 386 times
Capture force and disp.PNG
Capture force and disp.PNG (64.9 KiB) Viewed 386 times
Capture force disp in member.PNG
Capture force disp in member.PNG (80.97 KiB) Viewed 386 times
Time history results are as below. The global displacement appears to keep increasing and not oscillating right from the start. Damping would be suspicious, but I have auto Layleigh specifying first and second frequencies, so it can not go wrong in my view.
Capture th failure messag.PNG
Capture th failure messag.PNG (47.89 KiB) Viewed 386 times
Capture th force vs disp.PNG
Capture th force vs disp.PNG (61.01 KiB) Viewed 386 times
Capture force disp global.PNG
Capture force disp global.PNG (53.6 KiB) Viewed 386 times
M10 - 6 storey -push over with beams.zip
(172.92 KiB) Downloaded 70 times
M10 - 6 storey -time history with beams.zip
(204.17 KiB) Downloaded 63 times

Re: SFI-MVLEM modelling

Posted: Wed Oct 02, 2024 8:51 am
by STKO Team
The concrete and steel models may have some congerence issues.
Try to handle them by using a smaller initial time step (like 5000).

Regarding the dynamic analysis, can you check what happens if you make the damping proportional to the initial stiffness rather than the tangent stiffness.