关键词: 吸力式基础；鳞片式钢板结构；剪切应力；砂土；黏土；摩擦角；海上风电

Abstract: To improve the penetration and bearing performance of suction foundations in marine engineering, a novel steel plate structure with bionic snake-scale was proposed. By improving the traditional interface direct shear apparatus, interface shear tests were carried out on continuously arranged scale steel plate structures in sand and clay along the cranial and caudal directions of the scales, revealing the variation laws of peak shear stress and residual friction angle between the scale steel plate structure and soil under different normal stresses. The results show that: ① The peak shear stress along the cranial direction in sand and clay is approximately 14%-65% and 5%-86% higher than that along the caudal direction, respectively. ② When the normal stress reaches 50 kPa, the peak shear strength of the scale interface in sand is 62.41% higher than that of the smooth interface. ③ In clay, with the increase of consolidation pressure and normal stress, when the shear direction changes from caudal to cranial, the peak shear strength and residual stress of the interface increase, and strain softening occurs in clay shear. ④ There are significant differences in the peak and residual friction angles between the scale and smooth steel plate structures in clay, but the shear direction has little effect on them. ⑤ To achieve the effect of penetration resistance reduction, it is necessary to weaken the shear effect between soil particles, so the outer wall of the scale suction foundation should be arranged at intervals. The relevant results can provide reference for the design of various pile foundations in marine and hydraulic engineering.

Key words: suction foundation；scale steel plate structure；shear stress；sand；clay；friction angle；offshore wind power