Response of Monopile Offshore Wind Turbine Structure Subjected to Seismic Loads and Degradation

Abstract

The objective of this work is to analyse a monopile offshore wind turbine structure subjected to the coupled loads originating from wind, soil interactions and possible seismic activities. The monopile support structure is designed to be installed at 25 m water depth to support a 5MW wind turbine. The structural assessment is performed based on the finite element method accounting for the nonlinearities associated with the geometry and material. The nonlinear structural response of the monopile structure during the seismic activity is assessed accounting for the time-variant degradation of the load-carrying capacity due to corrosion. The nonlinear response of the degrading structures at different years of the service life is presented.