The revealing of a regression dependence of the profile length of the rock discontinuity on the joint roughness coefficient

The present work is devoted to revealing the regression dependence of the discontinuity profile length (L) on the joint roughness coefficient (JRC). Involving the profile scale data of Barton–Choubey and subsequent statistical analysis, a forward and inverse regression relationships between the values of JRC and L are obtained in the form of the third degree polynomial functions. Using the 3D scans of rock sample joints (obtained from the Brazilian test) and inverse regression relationship “L versus JRC”, the variability of the joint roughness coefficient over the entire cleaved surface is shown. For a generalized roughness assessment, it is proposed to use the mean value of the joint roughness coefficient.