Abaqus, using nonlinear spring to create tensionless soil.

[hunnyahmed12]

I am creating tensionless foundation for rigid pavement using nonlinear spring. I am trying to achieve spring response in compression only and no response in tension. To create this i am assigning stiffness value in the form of (displacement, force) in input file however I am unable to make it work. It gives alot of numerical singularity and eigen value problem whereas the same model with normal stiffness value works fine. Please guidance required urgently.

 

[FEA way]

You could use GAPUNI elements for that. They are like compression-only springs (simple contact elements).