Joint Roughness Coefficient Test Device (Tilt Test)

Used to calculate the JRC of a rock or joint. The device consists of an adjustable inclined plane, on which the rock sample (100 mm max dia.) is placed, separated along the surface where the roughness is to be measured. Then the plane is slowly tilted until sliding of the upper part of the sample on the lower one occurs. From the measured inclination angle it is possible to evaluate the roughness index.