A New Method for Determination of Joint Roughness Coefficient of Rock Joints

Abstract EN

The joint roughness coefficient (JRC) of rock joints has the characteristic of scale effect.

JRC measured on small-size exposed rock joints should be evaluated by JRC scale effect in order to obtain the JRC of actual-scale rock joints, since field rock joints are hardly fully exposed or well saved.

Based on the validity analysis of JRC scale effect, concepts of rate of JRC scale effect and effective length of JRC scale effect were proposed.

Then, a graphic method for determination of the effective length of JRC scale effect was established.

Study results show that the JRC of actual-scale rock joints can be obtained through a fractal model of JRC scale effect according to the statistically measured results of the JRC of small-size partial exposed rock joints and by the selection of fractal dimension of JRC scale effect and the determination of effective length of JRC scale effect.