Interaction between concrete and rebar

[Telec]

Hi,
in stko \ opensees is there a way to model a concrete shell element and separate reinforcing bars with beam elements and then connect them together making them interact?

For example, inserting a beam element with nodes shared with the shell element and using a beam offset?
Or using a node-to-node link interaction
thx

[Clarabella]

Dear Telec,
thank you for your question, we have been working a lot with solid models and bar slip.
You can either use BeamSolidCoupling (full composite action) or BeamToSolidBarSlip (if you want to model slip).
Please see the manual at page 98 and 99: https://asdeasoft.net/pdf/MANUAL_STKO_29_10_2020.pdf
Best regards

[Telec]

OK thanks. However, using the BeamSolidCoupling I can model the interaction between a beam element and the face of a solid. If I understand correctly, with the beam element perpendicular to the face of the solid. But if instead I wanted to model the interaction between beam elements parallel to a face (not a face of a solid but only a faces geometry), exactly like the steel bars in a concrete plate, can I still use the beamsolicoupling? Thanks

[STKO Team]

using the BeamSolidCoupling I can model the interaction between a beam element and the face of a solid

Not necessarily. The "Beam-Solid" term simply means the it is able to create a rigid-link between a master node whose DOFs are those of a beam (Displacement+Rotation), and a slave node whose DOFs are those of a continuum element (Displacement).
So basically you can use it not only for a beam perpendicular to a solid-face, but also to embed a beam inside the solid-volume, or to attach a beam that lies tangent on the solid-face.

If instead you want to attach a beam (6 DOFs) to a shell (6 DOFs) you don't need the beam-solid coupling, because both master and slave nodes have the same DOFs (Displacement + Rotation).
In this case you can simply use on of the following methods:

• use a rigidLink if your beams are at a finite distance from the shell (for example a non-negligible offset of a deep beam from the slab above)
• use a equalDOF if your beams are at a zero distance from the shell (so that coupling between displacement and rotation is not necessary)
• the first two methods are necessary if you model the slab and the beams as separated geometries. Otherwise, you can simply merge them into a single geometry and assign the shell properties to the faces, and the beam properties to the edges

If you post a sketch of what you want to do, we can give you an advice on how to model it

[dudchenkoav]

Hello STKO Team!

In your youtube channel I saw an interesting simulation related to this issue:
https://www.youtube.com/watch?v=SiFcJBum1ts&t=36s
Is it possible to ask you about sending the model from the video to see how this can be implemented correctly in STKO?


Best Regards,
Aleksandr

[marafini.f]

Sorry for the late reply dudchenkoav,
here is a copy of all the files from the webinar you mentioned.

webinar_october_interactions.zip

(6 MiB) Downloaded 325 times

You will find two models, the 03_bar_solid_bar_slip/_2, they are the ones you are looking for.
Let us know if you need anything else.

Enjoy your modeling
Francesca

[dudchenkoav]

Dear Francesca,

thank you for your reply.

Best Regards,
Aleksandr

[marafini.f]

Happy I could help.
Best regards
F.