Numerical Modelling of Soil-Pile Interface Response

Many Offshore wind projects are being developed nowadays. Design of monopiles, the most used foundation system for the offshore wind turbines, requires a special attention in the characterization of the soil-pile interaction. The main feature induced by axial cyclic loading at the level of soil-pile interface is the decrease in normal stress. Hence, evolution of soil-pile interface normal stress may affect shearing mechanism of the pile. Using a finite difference software, this paper presents an alternative method to simulate the interface response. Curves illustrating the evolution of normal displacement in function of shear displacement, extracted from experimental shear tests, were directly injected as disturbed relative normal displacement in the interface nodes. Therefore, shear stresses of the interface nodes are directly corrected by equilibrium procedure, based on the principle of elasto-plasticity. Calculation results present good agreement with experimental results.