Element type for a non regular soil mesh

[psal]

Gentlemen
I have a semi-circular and linear disposition foundation. In order to model the soil, I draw each solid to fill the space between the foundation, but I have triangular solids.
I assigned the element properties of the soil as SSP Brick, like in the online tutorial ASDA Absorbing Boundary Conditions. As the brick element is an eight node hexahedron. I erase the triangular solid and mesh the solids with structure hexaedron linear to see if it runs, but the error keeps saying: Invalid type of element or number of nodes, and I will have at the end triangular solids (I left them in blank in these models)What do you suggest to make run this model considering the interaction of the soil? Do I have to change the element properties to another? Do I have to do the mesh in a different shape?
Thanks for your help.

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Captura de pantalla 2024-09-09 201555.jpg (389.67 KiB) Viewed 3141 times

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[STKO Team]

To make sure STKO is able to mesh all your solids as Hexa, you need to make sure your geometry is made of 6-faces volumes.
If you cannot do that, just mesh it with tetra unstructured mesh and use a Tetra element

[psal]

I remesh again with 6 faces elements, so I can still use Blocks. (photo 1)

Now, when I merged this mesh followed by the command "Build the mesh", many soilds disapear and ther turn ligh gray, showing only the nodes. (photo 2)

When I used compound, they all keep together, but to have the soil interaction effect, I need to merged them, righ?

Can you help me, what I am making wrong?

[STKO Team]

Sorry but looking at picture1 I can see many volumes that are not 6-faces (top-bottom-front-back-left-right):

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[psal]

Thanks for the observations.

I think I almost did it, because it let me merge the soil layer, and when I mesh it, anything disappears.

Now my questions are: I have an space that is a triangle, ¿Can I use both type of shapes in the same model? This is, can i use de SPP Block and a tri31 or a simple contact 3D?

When I run the model, the period of the structure is getting weird with values on the fundamental period equal to 100. When it displays the masses, it is showing tons that were not in the original model, I guess this is why the period is weird.

¿Can you give me a hint what is happening when I run the model with the soil interaction? I used the soil properties recommended in the open sees help. I am attaching the model if you have a chance to see.

Thanks in advance

[STKO Team]

If you plot the modes of vibration you will realize what's going on:

modes.png (205 KiB) Viewed 2988 times

Your soil layers are not attached to each other.

Another issue:
Pay attention to the units. You are working in N-mm, your mass density should be of the order of 1.0e-9, NOT 1.0e-5!

[psal]

thanks for your help.

[STKO Team]

You're welcome