Soil-monopile interaction assessment of offshore wind turbines with comprehensive subsurface modelling to earthquake and environmental loads of wind and wave

Abstract

The dynamic soil-structure interaction characteristics of MOWTs (monopile offshore wind turbines) constructed in complex ground conditions, including three-dimensional (3D) geomorphological variation, change of faults and geomorphological deformation, was investigated first time in literature with the presented paper using the finite element (FE) analyses. The FE models are built utilizing the robust image processing technique based on the data obtained from seismic profile field survey to incorporate complex sedimentological and seismostratigraphical evidences. In the 3D FE analyses the hypoplastic constitutive model is considered. The validation is carried out by comparing the results of the simulation with the literature. The soil-monopile-turbine interaction behaviour based on the non-linear time history responses under bilateral seismic excitation and environmental loads of wind and wave are investigated. It is concluded that dynamic response of the monopile system and soil-monopile-turbine interactions are significantly influenced by geomorphological subsurface variations. It is thus critical to take into account the 3D variations of sedimentological faults and deformations as identified through the seismic field survey in the context of 3D FE analyses.