Technical Inquiries from Webinar: Transition Interaction and Embedded Element Constraints

[liushun]

Hello STKO team,

Thank you very much for your continuous support.

While studying the webinar (#025 New Element Presentation - ASDAbsorbingBoundary), I encountered some confusion regarding the creation of the Transition interaction (the connection between the surrounding soil and the soil enveloping the structure). Specifically, the master entity was selected as the surrounding soil elements, rather than the contact surface. What are the differences between these two approaches?

Additionally, the slave entity was chosen as the contact surface of the soil enveloping the structure. Are there any important considerations when partitioning this part of the soil? For example, should the size of this slave soil region be significantly smaller than the overall model dimensions, and must it fully envelop the underground structure?

I also have a question about the ASDEembeddedNodeElement constraint: what impact does it have in dynamic analysis? I did not fully grasp this part in the subsequent discussion during the webinar and would appreciate your support.

Thank you very much for your help. I look forward to your reply.

[STKO Team]

While studying the webinar (#025 New Element Presentation - ASDAbsorbingBoundary), I encountered some confusion regarding the creation of the Transition interaction (the connection between the surrounding soil and the soil enveloping the structure). Specifically, the master entity was selected as the surrounding soil elements, rather than the contact surface. What are the differences between these two approaches?

The slave geometry is the one that will contain the slave nodes (the ones that have to be EMBEDDED). I want to embed the only the nodes at the contact in the transition zone. So I select the inner SURFACE.
The master instead is a collection of ELEMENTS that should EMBED the slave nodes.
In this case the elements are 3D, so I select the outer solid domain.
https://opensees.github.io/OpenSeesDocu ... ement.html

Additionally, the slave entity was chosen as the contact surface of the soil enveloping the structure. Are there any important considerations when partitioning this part of the soil? For example, should the size of this slave soil region be significantly smaller than the overall model dimensions, and must it fully envelop the underground structure?

In general the slave should have a finer mesh, because each slave node should be EMBEDDED into the nearest MASTER element.
If the MASTER is finer, then there will be interpenetrations

I also have a question about the ASDEembeddedNodeElement constraint: what impact does it have in dynamic analysis? I did not fully grasp this part in the subsequent discussion during the webinar and would appreciate your support.

It's a penalty-based constraint. So just pay attention not to choose a too high penalty value