Abstract：At present，there are few studies on the horizontal load behavior of large-diameter rock-socketed single pile foundations for offshore wind turbines, and it is difficult to consider the impact of rock foundation breakage on the bearing performance of foundations in traditional numerical simulations, so the failure mechanism is still unclear. In order to solve the difficulties in accurate numerical simulation and analysis of horizontal bearing characteristics of large rock-socketed monopile foundations for offshore wind turbines. Firstly，according to the geological survey data of the offshore wind field，the finite-discrete element method(FDEM) was used to study the mechanical properties of the weathered granite in the rock seabed. Then we improved the algorithm of mesh remeshing and contact detection in the FDEM program，and realized the embedding of cohesion elements in the pile-rock interface. Based on the self-developed FDEM preprocessing program GiD–Y2D，we established the FDEM plane strain model of the pile-rock interaction of offshore wind turbines. Finally，we analyzed the failure mode of the pile-rock contact interface of the offshore wind turbine and the horizontal bearing characteristics of the rock-socketed pile foundation. The results show that the failure modes of rock seabed can be divided into tension failure stage and compression failure stage. When the tension zone is damaged，the horizontal displacement of the single pile is about 1.37×10－4 times the diameter of the pile. After local failure，the lateral capacity per unit length decreases by about 30%，and the lateral capacity stiffness decreases to 2/5 of the original. When the compression zone is damaged，the horizontal displacement of a single pile is about 2.17×10－3 times the diameter of the pile. After the failure，the foundation reaches the ultimate lateral capacity. Due to the brittle failure of the rock mass around the pile，the lateral capacity per unit length of the pile decreases rapidly by about 62.7%.
张柏楠1，韩 勃1，代 松1，何 奔2，赖踊卿2. 基于FDEM的大型海上风机嵌岩单桩基础水平承载特性研究[J]. 岩石力学与工程学报, 2023, 42(S1): 3309-3323.
ZHANG Bonan1，HAN Bo1，DAI Song1，HE Ben2，LAI Yongqing2. Research on the lateral capacity characteristics of rock-socketed single-pile foundation for large offshore wind turbines based on FDEM. , 2023, 42(S1): 3309-3323.
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2023, Vol. 42 
