Application of 3D rough discrete fracture networks to fluid flow processes in fractured rock masses

Discrete fractures are pre-existed in rock masses, which have been proved influencing the mechanical behaviours of rock masses. Modeling the network of discrete fractures is a crucial aspect in studying fluid flow within fractured rock masses. A three-dimensional rough discrete fracture network (RDFN3D) model, developed using the three-dimensional fractal Weierstrass-Mandelbrot relationship and compared with the discrete fracture network (DFN3D) model, was discussed in terms of its influence on both 2D and 3D structural models. The methodology for modeling RDFN3D based on MATLAB code was described. The impact of fracture roughness on seepage characteristics was analyzed and compared for both RDFN3D and DFN3D models. Results indicate that rough structures have a significant effect on the seepage behavior in rock masses. Differences between flow velocities of DFN3D and RDFN3D models increase with increasing pressure gradient and fracture width. Fluid flow velocity in rough structures is lower than that in DFN3D models, which becomes increasingly evident with growing flow pressure and joint aperture.