A New p-y Curve for Laterally Loaded Large-Diameter Monopiles in Soft Clays

In harsh offshore environmental conditions, the monopile foundations supporting offshore wind turbines must be designed for lateral loads such as winds, waves, and currents. The Beam on Nonlinear Winkler Foundation (BNWF) method has been widely used because of its clear concept and lower calculation cost. The selection of a reasonable p-y curve is critical to the calculation accuracy of this method. This paper clarified the defects of widely used API p-y curves for soft clays and then proposed a new p-y curve with better versatility and applicability. The suitability of the proposed p-y curve was validated by comparing it with the calculation results from the three-dimensional finite element method (3D FEM). Compared with the API p-y curve, the proposed p-y curve can better predict the lateral behavior of large-diameter piles in soft clays, such as the load-displacement curve of the pile head, lateral deflection profile, and bending moment profile. The research findings can provide guidance for the design of monopile foundations supporting offshore wind turbines in soft clays.