Thank you for your quick reply,
It was actually very helpfull!
I have 3 concerns,
I changed the supports and the elastic ground definition, as the thread recomended, then I created a nodal load case, with a load going upwards and another going downwards because I wanted to see the soil reaction, and think it's perfect how it reacts (only on the downards load).
But I am not so sure about the values of the deformation of the beam on the upwards load, I think the deformation is too small and the fact that there is no displacement at the end of the beam even if I have no support there, does it has to do with the active unidirectional Kz +Uz?
Also i have 2 errors of non linear convergence as you can see on the screeshot, on the case number 2, I asumed it was because there is only an uniform upwards load of +10KN.
And I didn't have any supports to block that reaction, and so I applied a roller and I had the same errors.
And this also aplies to the point loads (Load case 3).
I would like to fix this errors, and also i would like to ask for a detailed explanation of the unidirectional uplifting similar to this, wich I found so nice and clear about the supports. (because I dont understand if they are blocking it or allowing it?)
"In a 3D model you have 6 degrees of freedom: 3 translations UX UY UX and 3 rotations RX RY RZ. To calculate a structure (whatever it is including a beam on elastic soil) you have to provide restrains for all of them as otherwise it will either move way or spin.
When you define UZ elastic soil you blocked two of them (UZ and RY) but still you need to take car of the others. If you define UX and RX support in one node you dealt with the next two. Now you have to think about horizontal displacements and rotation about the global Z which means either UY support in two nodes (or UY and RZ in one) or UY elastic soil along the beam"
Thank you very much in advance!
