Mesh size for foundation slab on springs

[dgerashki]

Hi all,

I am modeling a foundation slab on area springs. The thickness of the slab is 1.2m. I use a mesh size of approximately 0.5m.
Is there any limits for minimum mesh size dependent to the slab thickness when the supports are springs?
I know that for a floor slab the results are adequate for a span to thickness ratio of 5:1, but I am not sure what is the span length on spring model. Can it be taken as the dimension between the columns as per traditional calculations for foundation slabs?

Thanks in advance!

 

[salah0]

the precision of calculation is better with small size mesh, and the only way to see the behavior of your slab is to put joint with spring between column and wall etc...
The precision increase with decrease of size mesh.

 

[bgatto]

For such a thick foundation I usually use 3D elements (solids). In your case it would be 3 layers x 0.40 m or 4 layers x 0.30 m. The XY size of the solids would be adequate (0.30`0.50 m)