Fig. 3

Schematic of the setup used for measuring the internal friction coefficient of ground olive residues; (A) Assembled double-ring shear cell; (B) Individual components of the shear cell: (1) A pulling mechanism applying horizontal force via a wire connected to a digital force gauge, (2) An upper cylinder open at both ends, (3) Calibrated weights to apply normal force, (4) A cylindrical container holding the sample, and (5) A lower cylinder closed at one end.