Extreme Element Distortion in coupled structural-acoustic analysis

[aurum]

I'm studying the response of a dam-reservoir-foundation system to earthquake excitation using coupled acoustic structural analysis method. However, the analysis is aborted due to extreme element distortion. The distortion looks unreal. I'm attaching the picture of it below. What are the possible checks I'm missing? Any assistance is appreciated.

 

[FEA way]

Check if there are any other errors/warnings in .msg and .dat files. Make sure that your boundary conditions, loads, interactions and material properties are correct (double-check the units too).

It would be best if you attached your model here (.cae or .inp). Otherwise please describe it with more details and show the set up (boundary conditions, loads, interactions, etc.) on additional pictures. This will help us find the solution to the problem.

 

[aurum]

I've increased the mesh size in the dam structure and distortion has been taken care of, but the solution seems to be not converging. A trivial nonlinear problem.

Is it because of the constitutive model, boundary conditions, interactions or something which I'm unable to figure out? I would like to share my file but it's too big for the attachment here. How do you share it?

Thanks in advance.

 

[FEA way]

If the .cae file is too big you can attach .inp file. Otherwise please share some pictures showing the whole model along with mesh, boundary conditions and interactions. Short description of the features used in this analysis will be necessary too.