asdeasoft.net

Dear Francesca,

Got it! Thank you.

Bence

STKO Team wrote: ↑

Fri Jul 23, 2021 8:55 am

I would like to thank you for your assistance and guidance, and to tell you that analysis run and complete successfully after doing the modifications.

You're welcome

Please, could I ask you about the penetration between lateral sides of foundation and surrounding soil? When the magnitude of acceleration is displayed together with displacement for deformation, there is no penetration. However, the left side of foundation penetrate the soil when acceleration is used for deformation.

It makes perfect sense. Penetration is related to displacement (not velocity nor acceleration). A simple example is a contact between 2 nodes: Node_1 (at position X = 0) is fixed, so its displacement Ux(t) = Ux(t+dt) = 0, and therefore its first and second derivatives with respect to time are both 0 (velocity and acceleration). Node_2 (at position X = 1) has Ux(t) = 0 and Ux(t+dt) = -1 (displacement at which contact happens), so its velocity is not zero, but -1/dt.

have used the frequencies (f1, f4) of the first two modes in the X direction of the fixed structure (using ETABS) to calculate Rayleigh damping for structure and foundation.
I have used the frequencies 0.2 and 20 Hz to calculate Rayleigh damping for soil.
Please, could you tell me if you have any notice or correction for these chosen frequencies? Could you suggest a reference to get a benefit?

Here is a reference about damping (rayleigh and numerical damping) for soils:
https://geotechsimulation.com/2018/04/0 ... -analysis/

Dear STKO Team,
Thank you very much for your assistance and prompt reply.
I noticed that no strain displayed in soil surrounding the foundation. Could I ask you what’s the problem, please?
Best Regards,
Rania

This is strange... can you share your model here?

Dear STKO Team,
This problem exists in the both cases of the presence and absence of the building. However, it becomes more clear when the foundation is present only without the building, so I send the relevant file.
I will be grateful for any help or information you can provide.
Yours Faithfully,
Rania

Dear Rania
You're lucky! we just identified the issue another user had in the forum.
check the solution here:
viewtopic.php?f=27&t=2015&p=3954&hilit=partition#p3954

Dear STKO Team,
Thank you very much for your reply.
I have checked the proposed solution, and used 2 recorders for 2 regions: (soil) and (structure/foundation). This method works just for nodal results. Unfortunately, it doesn’t work in my model for element results such as stress, strain, section force, etc., where the (structure/foundation) model is omitted from the render window with error message in the terminal bar (Error: One of the partitioned DB is null or invalid).
I was wondering what the difference in my model is. Could you help me to resolve this issue, please?
Kind regards,
Rania

You are right,
we have identified the problem and it will be solved in the next (2.0.4) version.

The problem is that the foundation is so small, that it appears only in some of the 8 partitions (1,2,5, and 6), while it is not in partitions 0,3,4 and 7.
You can see it when loading the database for the foundation. You will see 4 error messages saying that some of the database cannot be opened (error in red).

Now you can solve it manually.

You can delete the MPCO files (before importing them into STKO) that generated that error. In your case 0, 3, 4 and 7. The you can load the MPCO files and it will work

Dear STKO Team,
It’s done. Thank you very much for your reply and efforts.
Best wishes,
Rania

You are welcome!