Surface roughness analysis of rock joints based on a 3D surface model

The morphology of rock fractures plays an important role in the mechanics, hydrology and coupled hydro-mechanics of rock fractures. In this paper, surface roughness numerical analysis and scale effect of rock joints based on the three-dimension morphology of a fracture is studied. Firstly, random fractals and GIS-DEM are applied to simulate and describe the 3D morphology of a rock fracture. Then, this study proposes a method of numerically simulating and analyzing the 3D surface and aperture of a rock fracture. Based on the theory of Belem et al, this study simplifies and revises the 3D surface angularity theta(s), the apparent anisotropy of the surface K-a and the surface Z2 parameter Z2(s) then applies the 3D roughness coefficient surface JRC, the 3D surface average angularity in shear orientation theta(s)' and the apparent anisotropy of the surface k(a)' to assessments of the roughness of rock fracture surfaces.