The basics of pile foundations are explained in the following tutorials.
www.sofistik.com > Infocenter - Overview > Documentation - Tutorials > Geotechnical Engineering > Halfspace Analysis for pile foundation
I am not sure how detailed you want to model the pile. If you are working with springs, you can set the axial failure load to 0 (activate nonlinear spring behaviour → Nonlinear calculation with ASE).
If you want to work with a material bedding, you have to set the tensile strength to 0 MPa (New Material > bedding > activate).
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