Characterization of Joint Roughness in Granite by Applying the Scan Circle Technique to Images from a Borehole Televiewer

Excerpt

Joint roughness directly affects the mechanical behavior of a rock mass and the fluid flow through joints. The Joint Roughness Coefficient (JRC) is one measure of this roughness and is a key parameter for rock engineering works as it provides insight into the shear strength and deformation behavior of rock joints. Generally, a JRC value can be obtained from a roughness profile through the qualitative comparison of the ten different standard profiles for joint roughness and defined within the range 0–20 (e.g., 0–2, 2–4, etc up to 18–20) (Barton and Choubey 1977). Roughness profiles which are compared with the standard profiles are often obtained from outcrop or drill core using a variety of techniques. For instance, the joint roughness profiles have been obtained including photo-analysis techniques (Franklin and Maerz 1986; Franklin et al. 1988; Maerz et al. 1987; Unal et al. 2004) and laser scanning (Fardin et al. 2004). These techniques are suitable for use on a small number of samples and data depending upon various circumstances in either the laboratory or the field. …