Nothing to regenerate error

[EngUnCa]

Dear STKO team,
i am very sorry that i met different problems in different files and please, i need your help: i have three files that were provided to me externally, and when i try to open these files i read a series of errors (difficult for me to interpret) following a "nothing to regenerate" warning. Is it possible to recover these files?
As an example, i provide a screenshot of the type of error.

Thank you for your support! Best wishes

[kesavapraba]

I also faced the same issue sometime back, but unfortunately I could not recover the files.

[STKO Team]

Unfortunately the file seems corrupted for some reason and cannot be recovered.
Try to understand why it may be corrupted. Did STKO crash while saving it? Did you download those files and got corrupted during the upload/download?

[EngUnCa]

Good morning, the zip file was provided to me externally by a member of STKO Team (i suppose) in order to be able to study it for my thesis work, via a Dropbox link. All i did was download the link that was provided to me in order to have the files available. Evidently the files were already damaged from the start.
Consequently i tried to rebuild the files. One of these is attached, so i wanted to ask: it takes a lot of time or my computer crashes during analysis, is there any way to improve my model to make it go faster?

My objective is to get the T1 curve and failure at the loading point
The measurements are in N and mm.

Thanks for your attention! Best wishes

[kesavapraba]

Hi, I would suggest you to use coarse mesh first, along with parallel solvers (OpenSeesMP), to speed up the analysis. You can fine-tune the analysis outcome once the coarse-meshed model runs without convergence problem.

[EngUnCa]

Good morning, thanks for your help! I managed to solve my problem but I still have an issue: in the first analysis step this sudden corruption occurs in the first analysis step.
How can I solve this problem? Are there problems with the stiffness of the bond between the beam and the support?

Thanks a lot for your assistance

[STKO Team]

Try this:

RotturaTaglioEstremità.zip

(1.25 MiB) Downloaded 209 times

I changed the contact at the supports. I made it node-element, the master is the support, and since it's assumed to be quite rigid, I used a very coarse mesh.
If you have some neoprene there you may want to adjust the friction coefficient.

You can do the same on top. I saw you modeled the neoprene, but keep in mind that here you are assuming linear kinematics, (no hyperelasticity at finite strain) so you will see the top plate compenetrate...

[EngUnCa]

Thank you for your answer! Unfortunately i was unable to solve my problem. The beam failure is ok but the displacements are too small if compared to the experimental results, which i posted previously.
How can i understand where to reduce the stiffness of the beam to obtain displacements like those in the previous graph? Thanks again!!

[STKO Team]

Can you post the load-disp curve you are obtaining? And also some images of the output?

[EngUnCa]

This is the load-disp curve, thank you!!