Figure 2
Schematic of a modified direct shear apparatus modified from22,34. For the interface tests and to accommodate snakeskin-inspired surfaces, the vertical stress application through the loading rod mounted on a steel ball and rectangular loading plate in the conventional apparatus is replaced by a rectangular loading plate attached to a vertical loading frame. For soil-soil tests, a circular shear box with a circular loading plate fixed to the vertical loading rod is used. Note that the loading plate and loading rod were not fixed in the conventional apparatus.
