Fig. 7

Indoor direct shear test instrument. (a) Side view; (b)Top view; (c)Ball contact between the upper shear box and the force measuring ring; (d)The relative position of the polyester film to the sample.

Indoor direct shear test instrument. (a) Side view; (b)Top view; (c)Ball contact between the upper shear box and the force measuring ring; (d)The relative position of the polyester film to the sample.