I am using ANSYS APDL to simulate soil-pile interaction. I choose Solid 185 for both pile and soil, applying Drucker-Prager model to simulate soil behavior. And I choose Contact 174 and Target 170 for contact elements. The problem is that I could not get convergence when doing the non-linear solution; while the solution would be convergent when I simply input elastic parameters for soil. Can anybody help me out with the problem and I would really appreciate your any tips. Thanks.