Invalid type of elements or number of nodes

[KarishmaN]

Dear STKO Team,
Thank you for your continuous support.
I have changed the model direction. However I still have problem with the analysis. I attached the new model here , please kindly review it at your earliest convenance time. I will greatly appreciate if you could fix the error in this model, since my free version is about to finish soon and if i couldn't model it successfully our department wont buy the commercial version for our research. Thank you very much for your understanding.
Regards,
Karishma

[STKO Team]

There were some issues in your model:

1. The error you get comes from an incompatibility between the element property (brick = hexahedron) and the mesh type (tetrahedron).

   

   ERR_1.png (336.06 KiB) Viewed 1443 times

   To mesh your model with hexa elements I had to add some internal cuts:

   

   ERR_2.png (181.64 KiB) Viewed 1443 times

   merge everything

   

   ERR_3.png (148.61 KiB) Viewed 1443 times

   and assign proper mesh controls

   

   ERR_4.png (176.59 KiB) Viewed 1443 times

Here's a fixed version of your file:

PrismTest4.zip

(1.76 MiB) Downloaded 170 times

I also made a finer mesh to capture the damage better and used OpenSeesMP for parallel computing.
Finally I applied an imposed displacement on top (with load control) instead of a force (with disp control) because with the force only, if the damage will be unsymmetric, the prism will rotate.

Here's what I get:

ERR_5.png (169.34 KiB) Viewed 1443 times

[alex.ivan]

Hi,
I also have the same problem with my model.
Could you please help me to detach the problem? I have attached the model.

[STKO Team]

You are using a Triangular mesh with a quadrilateral element (those are incompatible)
You either use a triangular mesh with a triangular element property (ShellDKGT, ASDShellT3)
or a quadrilateral mesh with a quadrilateral element property (ShellDKGQ, ASDShellQ4)

[Syun]

Dear STKO Team,
I also encountered the same problem.
I have checked the element properties that I assigned, it seemed to be right.
As for the geometry, I am not sure if there is something wrong.
Could you please help me to find the mistakes I made?
There are the error screenshot and my model file below.
Thank you very much!

[STKO Team]

Same error!
You are using the ShellMITC4 element on a triangular mesh.
You either make the mesh all-quad, or use the ASDShellT3 element

[Syun]

Dear STKO Team,

Thank you very much for your prompt response!

Following your suggestions, I have attempted to adjust the seeds and set the element to rebuild a quad mesh.
However, despite these efforts, the elements still appear as triangular meshes (as shown in Figure 1), and I am unsure how to resolve this issue.

Additionally, I also tried using the ASDShellT3 element with triangular mesh, but I encountered an error when running the analysis (as shown in Figure 2).

I have attached the model file for your reference. I would greatly appreciate your assistance in resolving this matter.

Thank you very much for your time and support. I look forward to your response.

[STKO Team]

An all-quad mesh is guaranteed only if you have 4-sided surfaces (which is not your case).
Use the ASDShellT3, but make sure to use the latest opensees (3.7.0) (we added it recently):

https://www.researchgate.net/publicatio ... r_OpenSees

[allijkunz]

Dear STKO Team,

I am having the same error with my model, and I was wondering if you could help me find how I can fix it? I am using quadUP elements with a structured quadrilateral mesh to try to model a soil column, and I am not sure if I need to change something about the mesh or if there is some other problem that is causing the error

Here is my model so that you can take a look

FreeField.zip

(223.91 KiB) Downloaded 21 times

Thanks,
Allison

[STKO Team]

The file you attached is corrupted and cannot be open