Abstract: The problem of interaction between soil and supporting structure has aroused the attention of scholars, and the research on this field has also a new breakthrough. However, considering the thickness of the contact surface of pile-soil interaction, whether for the establishment of the computational model or for the selection of computational method, it is still open to question. After considering the thickness of the contact surface, the rigid plasticity theory is used to simulate the soil mass of pile, and the soil with the series of spring elements in the plastic area is simulated. On the basis of this method, the flexural differential equation of pre-stressed bolting pile is derived, and the finite difference method is used to calculate the internal forces of the pile body. Combined with the practical engineering, PLAXIS software is used for numerical validation, and the bending moment of pile compared with that using the above method. It is that found the results are slightly larger than the simulation ones. The reason may be that the series of spring number is not enough, indicating that there will be an optimal value for the spring number. Through the comparison analysis, the feasibility of the computational model is further illustrated.