Reliability analysis of monopiles for offshore wind turbines under lateral loading

This paper presents reliability analysis of monopile foundations for offshore wind turbine applications, along with probabilistic characterization of the responses. Finite element simulations are conducted using the PLAXIS 3D platform, where the monopile is modelled as a volume pile with dummy embedded beam elements. Sensitivity analyses are performed to identify the parameters that have the greatest impact on the responses due to the presence of uncertainties. To select the appropriate method for reliability analysis, reliability index values obtained from different methods are compared with those obtained from Monte Carlo simulation technique. Twelve different geometrical combinations of the monopile foundation are considered in the study, revealing noteworthy differences in design requirements compared to deterministic analyses. The reliability index values are found to be non-uniform and vary drastically with the expected performance level of the system. To further characterize the responses probabilistically, the Kolmogorov-Smirnov test is employed. The methodology presented in this paper provides valuable insights into the effects of uncertainties in design parameters on the responses of the monopile system, aiding in substantiating the reliability of the foundation design.