Concrete modal simulation

[davidrdguez]

Hi there,

I was asked to make a simulation of a reinforced concrete block (16x10 m2)in 3 thickness: 1.0 m 1.5 m and 2.0 m in order to choose the optimum value

This turned out to be more complicated than I expected.

I made some assumptions. The first one the concrete is isotropic in all the dimensions (since it's reinforced with steel)

Then I made a pre structural simulation taking into account the density and a usage load of 1000Kg/m2

Finally the modal analysis.

Results are weird, and the reason must be the fact I fixed the bottom face, which is not true.

I need to fix something but I don't know how to constraint it

Maybe adding another part around (soil) and making contacts?

How do you think I can approach this?

Thank you in advance
regards,