Coupled RC Core Wall with MVLEM-3D

[kesavapraba]

You are welcome.

[STKO Team]

This is the script for the section cut:

SectionCut.zip

(5.79 KiB) Downloaded 321 times

Now we are implementing it directly in STKO to make it more efficient and user-friendly. But in the meantime, you can use this.

Note:

• Run the analysis asking for "force" result (i.e. forces at the element's nodes). They are necessary to compute integrals for section cuts

When you run it, it will prompt you to provide necessary information

First, you have to select 2 points (for line cuts on shells) or 4 points (for plane cuts on solids).
This works best with structured quad/hexa meshes because you need all element boundaries to be on the cut plane.

SC1.png (146.73 KiB) Viewed 3217 times

Then you will be asked to optionally rotate the local axes for integration. You can select the axis and the angle of rotation. You can repeat it as many times you want to get your proper orientation. When you're done, press cancel to move to the next action.
Keep in mind that the local X-axis must be:

• On the plane of the shell. In this case the elements considered for the cut will be those in the opposite direction of the local X axis
• The outward normal for plane cut in solids. In this case the elements considered for the cut will be those in the opposite direction of the local X axis

  

  SC2.png (260.69 KiB) Viewed 3217 times

  When you're done you will be ased to choose the output of results in the Local system (the one you set-up before), or in the global.

  

  SC1.png (146.73 KiB) Viewed 3217 times

After that you will be asked to choose the results you want to integrate (keep in mind that if you mix solids and shells you will have multiple force results... select all of them if you want them all, or do it separately, it's up to you).


Finally you will be asked to ouput results only at the last step, at the last step of each stage, or for all steps.
Results will be printed in the terminal

Enjoy and let us know.

[kolozvari]

Hello, I am just following up on this older post and I was wondering if you have implemented section cuts in STKO yet? If so, can you please point me to the right documentation and examples.

thank you

[kolozvari]

hello,

so I was playing with the section cut python code you provided, but all my forces seem to be zero, which is definitely not the case.

Screenshot 2024-10-18 145938.png (909.17 KiB) Viewed 1803 times

I checked "force" in the recorder definition, but I am wondering is something else needs to be selected for MVLEM-3D elements. Can you please clarify?

Also, how do I get the forces for the entire RC core, which is not just a line element, but a box section?

Thank you!

[STKO Team]

We are working on including the section cut directly in STKO in a more flexible way.

Regarding the current implementation, it's not working with the MVLEM_3D because it does not handle "force" in the setResponse method (instead it works with the SFI_MVLEM_3D).
So you should re-run the analysis, setting a custom element result string in the MPCO Recorder, using "forceG" or "globalForce"

[kolozvari]

Thanks. Do I do that using custom recorder? Also, what about my second question about getting forces out of a box section?


Thanks

[STKO Team]

You should put it in the list of custom element responses in the MPCORecorder.
As you know, in OpenSees there's not a unified list of element results as per nodal results (they depend on the element/section/material...), So the MPCO Recorder interface in STKO has some common results as built-in checkBoxes. Any other response can be written in the custom element list:

mpco custom.png (36.87 KiB) Viewed 1797 times

Also, what about my second question about getting forces out of a box section?

Just select 4 points instead of 2:

boxcut.png (167.42 KiB) Viewed 1797 times

[kolozvari]

Hello,

Thank you again for providing the Section_Cut.py file for extracting section cut forces. I was able to modify it successfully to suit my use for the most part. I have two issues currently with the present code.

1) It appears that is one case when current code does not work well. Consider the building plan as shown below.

Screenshot 2024-12-28 103641.png (23.16 KiB) Viewed 1706 times

The plan of the building is such that it is not possible to select 4 nodes to define a section cut that will take into account all elements in the floor. See below as an example. No matter which 4 nodes I select, some columns will not be considered.

2) I am trying to extract forces in walls and columns only, but I also have a diaphragm in the model (see screenshot below).

Screenshot 2024-12-28 104253.png (432.02 KiB) Viewed 1706 times

Can you please confirm that section cut forces will be calculated only based on vertical elements (walls and columns indicated in red) and will not consider slab elements? This is what I need, but I am not sure if forces in slab elements will also be considered since it appears that nodes corresponding to slab elements are also selected.

Can you please suggest how to modify current code to address the above two issues?

Looking forward to hearing from you.

Thank you

[kolozvari]

Hello, I just wanted to follow up on this issue with the section cuts described above. I look forward to hearing from you.

Thank you

[kolozvari]

Hello, I am following up again on this issue with the section cuts. I am excited to hear from you.

Thank you