关键词: 钻井船插桩, 不同土层条件, 耦合欧拉-拉格朗日（CEL）方法, 贯入速率, 欧拉体范围, 网格尺寸

Abstract: According to the simulation of centrifuge model test of spudcan penetration in various soil profiles, several influencing factors of the penetration resistance are discussed using coupled Eulerian-Lagrangian (CEL) finite element method. Five typical seabed profiles commonly encountered in the field are considered: clay, sand, clay overlying sand, sand overlying clay, and layered soils. It is shown that different ranges of Eulerian domain barely affect the calculation results. To ensure the accuracy of the numerical results of CEL, fine mesh is defined near the spudcan and coarse mesh far away. For various soil profiles, the study confirms that decreasing the size of fine mesh or increasing the range of fine mesh can ease the vibration of the penetration resistance curves. By comparison, the size of fine mesh is proposed to be set as 0.05 times the diameter of the spudcan, meanwhile, the range of fine mesh is proposed to be set as 2 times the diameter of spudcan for various soil profiles. When the displacement control is adopted, the penetration rate has a little effect on the profile of clay, while a great effect on the profile of sand overlying clay. By comparison, a penetration rate of 0.2 m/s is selected in FEM when investigating the calculated penetration resistance in various soil profiles.

Key words: spudcan penetration, various soil profiles, coupled Eulerian-Lagrangian (CEL) method, penetration rate, Eulerian domain range, mesh size