Evaluation of p-y Approaches for Large-Diameter Monopiles in Sand

摘要

For the design of monopile foundations, the soil resistance is usually modeled by the subgrade reaction method. The commonly used p-y approach described in the offshore guidelines is generally assumed to be sufficiently accurate for slender piles with diameters D <= 2 m. However, several investigations indicate that the pile deflections of large-diameter monopiles are underestimated for extreme loads but overestimated for small operational loads. A three-dimensional finite element (FE) model is presented to evaluate the currently used p-y approach for piles in sand under static loading conditions in dependence on the pile dimensions and the soil's relative density. In addition, modified p-y formulations to account for the effect of the pile diameter are compared to the FE results.