Learning Forum

[Maryam Tabbakhh]

Hi,

I did some modeling with SSI capabilities in lsdyna. We had a response from a very large domain with SW4. I defined the DRM layer and added acceleration time history (obtained from the SW4)  at the interface between far filed and new filed soil layers and compared the results at some specific points. The results were very similar and there was a great agreement beween results.

now, I need to put the structure in the top of the soil. I am going to define the interface between soil and structure (regular one and not SSI because I already used the SSI interface at one side of my DRM layer and can't have two). I am going to define some coefficients and test the interface. The half of base of the structure is embedded in the soil. 

 

My questions are:

1-how can I verify my PML elements work propely? 

2-Is the approach I explianed here is right?

3- For embedded structure, we just need to define the interface between soil and sturcture (horizontally and 2 verfically at both sides) ? Is there any other considerations that I need to take into account?

 

Thanks so much

[Ushnish Basu]

The INTERFACE_SSI denotes the interface between (a) the structure and the near-field soil (together the generalized structure), and (b) the far-field soil. It is assumed that the physical structure does not extend outside the near-field soil. 

For the interface between the physical structure and the surrounding soil, we can either merge the nodes or specify a contact interface between them using CONTACT_AUTOMATIC or CONTACT_TIED, as appropriate.

There should not be a need to verify the PML elements separately, unless you see some unexpeted, anomalous behavior.

[Maryam Tabbakhh]

Thank you very much.