REVIEW OF RESEARCH PROGRESSES OF THE QUANTIFYING JOINT ROUGHNESS COEFFICIENT

The joint roughness coefficient (JRC) method was suggested by International Society for Rock Mechanics to estimate joint roughness in 1978. Although this method is widely used in engineering practices, there is a shortcoming of subjectivity and experience relied on investigator. So, the research works about quantifying joint roughness were developed by authors in the world. In this article, firstly, we introduced the research progress about quantitative characterization on both joint profiles and discontinuities roughness, and summarized the results of relationship between the parameters and JRC. Secondly, we evaluated the essential properties and applicability of each parameter, pointed out the problems about the parameters in obtained process including sampling interval influence, deciding triangulation of an elementary surface and determining the weight of each parameter in the comprehensive parameters method. At the same time, we gave the author's ideas of solving the problems. In addition, we discussed anisotropy and size effect of surface roughness in detail, on which are focused by researchers. Finally, we predict that fractal dimension remain a method to describe surface roughness and 3D printing technology can be helpful to research anisotropy and size effect of rock discontinuities roughness.