Study On Design And Bearing Capacity Characteristics Of Suction Bucket-pile Composite Foundation For Offshore Wind Turbines

In today’s society,clean energy has been highly valued by countries all over the world.As a new type of clean energy,wind energy is widely used.The marine wind energy resources are rich and relatively stable,which is promoting the development of China’s wind power industry from land to sea.Due to the increasing water depth of the sea area where the offshore wind turbine is located,the load transferred from the wind turbine structure to the foundation also increases.In order to effectively control the horizontal displacement of the foundation,the method of increasing the size of the foundation is usually adopted,which increases the manufacturing and construction cost of the common fixed offshore wind turbine foundation and increases the construction difficulty.Based on the analysis of the characteristics of various offshore wind turbine foundations,the suction bucket-pile composite foundation is proposed,which integrates the characteristics of suction bucket and pile.In addition,the suction bucket can be used as the construction platform of pile foundation to reduce the construction cost.In this paper,the conceptual design,detailed design and horizontal bearing capacity characteristics of suction bucket-pile composite foundation for 5MW offshore wind turbine are studied:(1)The concept design of suction bucket-pile composite foundation is carried out,and its unique structure form,foundation construction process and advantages of suction bucket-pile composite foundation in horizontal bearing capacity are analyzed.(2)The distribution of earth pressure around the suction bucket-pile composite foundation under horizontal load is given.Based on the theoretical analysis method of horizontal bearing capacity of single pile foundation and suction bucket foundation,the calculation formula of horizontal bearing capacity of suction bucket-pile composite foundation is derived.(3)Based on the structural design parameters,the finite element analysis of the suction bucket-pile composite foundation structure of 5MW offshore wind turbine is carried out by using ABAQUS finite element calculation software.The horizontal bearing capacity characteristics of the suction bucket-pile composite foundation and the distribution of soil pressure around the suction bucket-pile composite foundation under horizontal load are studied,and the rationality of the horizontal bearing capacity calculation formula derived in this paper is verified.