Weird Deformation at a sliding surface

Project Support
1

Hi

I am solving a solid mechanics deformation problem. In which I am getting unexpected deformation at two locations on the surface of body 1 (see attached pic). The underlying body is not deforming at all, and I am not sure how the top body is deforming through the underlying body 2, only at specific locations.

It is the run 2 of a sub-simulation named “Copy of Cascadia Q“ from the project linked here link.

Thank you

Viven

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2

Hi,

Is the first column for the pressure BC supposed to be X [m]? From your setup it feels like you wanted to go for t[s] instead.

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PS: how are you defining the material properties for these volumes, in particular creep for the first material? The material definition is quite odd, with 0.5 Poisson’s ratio (i.e. incompressible material) but a very high Young’s modulus and creep at the same time.

3

Hi

First, the pressure term is correctly applied in the X direction. Second, the material properties are also correct.

However, my question remains unanswered as to why the upper volume is deforming through the lower volume?

4

You’re seeing this huge belly because you are magnifying the displacement by 1e7 to 1e8 depending on the simulation run.

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5

Hi,

Thanks for your reply.
Could you explain why the overlying body deforms through the lower body, where the lower body is effectively rigid? This happens only in some random cases. In some other cases, it slides over the lower body as I want it to. This is weird because I am specifying sliding boundary at the contact with the lower body is having a high Young’s modulus, making it effectively rigid.

Even if it is due to high exaggeration as you mentioned, should not it be same for the lower body also?

Thanks

Viven