ABSTRACT
In the construction of offshore wind farms, foundation design for offshore wind turbines is one of the urgent points as offshore wind farms extend to deep sea areas and the larger wind turbine utilizing. Pile-bucket composite foundation is a useful way to support the larger wind turbine in the deep sea. In this study, the numerical models of monopile and pile-bucket composite foundations are developed by using ABAQUS. To present the superiority of pile-bucket composite foundations, these developed numerical models are used to perform a comparative study of capacity characteristics for monopile and pile-bucket composite foundations and analyze the seismic response of offshore wind turbine structures supported by monopile and pile-bucket composite foundations. The results show that the pile-bucket composite foundation can better utilize the bearing capacity of soil around the pile than the monopile. Furthermore, the seismic performance of the pile-bucket composite foundation is better than the monopile. the seismic response of offshore wind turbine turbines supported by a pile-bucket composite foundation is less than the monopile when applying the three different seismic waves. The decreased level is 32% and 22% and 8% in the displacement of wind turbine tower top, and 6% and 2% and 26% in the largest tilt of foundation on the soil surface.
