Influence of Seabed Characteristics on Cyclic Pull-Out Behavior of Suction Anchor for Floating Offshore Wind Turbine under Environmental Loads

This paper investigates the influence of sandy seabed characteristics on cyclic pull-out behavior of suction anchor for floating offshore wind turbine (FOWT) under cyclic wave loading on seabed and inclined environmental loads on padeye. The FE model in this study is developed by the combination of Biot's theory, linear wave theory, and the elastoplastic constitutive soil model. Wave-seabed-foundation interaction (WSFI) is validated by the means of centrifuge test results, while the available data on cyclic direct simple shear (CDSS) test of sands is used to calibrate the CycLiqCPSP constitutive soil model. Results reveal that presence of non-liquefiable layer surrounding the skirt tip increases the stability of anchor remarkably. Moreover, parametric studies demonstrate that changes in the seabed's sandy soil characteristics such as initial void ratio, shear modulus, and permeability can directly affect the further development of suction pressure beneath the anchor lid.