The study explores the effect of directionally dependent frictional resistances (frictional anisotropy) inspired by snakeskin patterns, on the behaviour of split set rock bolts. The patterns of the ventral scales of a snake are selected, and different models of patterns are developed by varying the scale angle. Split set rock bolts with these patterns are designed, and three-dimensional (3D)-printed using polylactic acid material. The 3D-printed split sets are tested for insertion and pull-out loads in cylindrical blocks made of plaster of Paris, using a modified universal testing machine. The results of the tests show that insertion and pull-out loads exhibit bilinear relationships with various scale angles (10°, 13°, 16° and 19°). The different scale angles induce different levels of wearing in the surrounding rock simulant during the insertion and pull-out, with a minimum at 16° and maximum at 10°. All the snakeskin-inspired patterns show significant frictional anisotropy. The study opens up possibilities for further research of snakeskin-inspired frictional anisotropy enhancement of split sets.

中文翻译：

---

受蛇皮启发的分裂式岩石锚杆摩擦各向异性行为模式

该研究探讨了受蛇皮图案启发的方向相关摩擦阻力（摩擦各向异性）对分裂设置岩石锚杆行为的影响。选取蛇腹鳞纹图案，通过改变鳞片角度开发出不同的纹样模型。设计了具有这些图案的分体式岩石锚杆，并使用聚乳酸材料进行了三维 (3D) 打印。使用改进的万能试验机，对 3D 打印的分体组在由巴黎石膏制成的圆柱形块中的插入和拉出载荷进行测试。测试结果表明，插入和拔出载荷与各种刻度角（10°、13°、16°和 19°）呈现双线性关系。不同的尺度角在插入和拔出过程中引起围岩模拟物的不同程度的磨损，最小为16°，最大为10°。所有受蛇皮启发的图案都显示出显着的摩擦各向异性。该研究为进一步研究蛇皮启发的分裂组摩擦各向异性增强开辟了可能性。