Fluid flow through fractured rock masses: Insight from single to complex fracture networks

To assess hydraulic properties of fractured rock masses, some key issues concerning fluid flow through fractures are reviewed and discussed. First, the derivations of fluid flow governing equations such as from Navier-Stokes equations to cubic law, as well as experimental and numerical methodologies for sample preparation, flow test, surface roughness generation, and flow simulation, are presented. Second, hydraulic properties of fractured rock masses without considering shear process, including permeability estimation, REV (representative elementary volume) calculation and determination of critical hydraulic gradient, are illustrated. Third, the effect of shear on fluid flow through single fractures, two-dimensional (2D) fracture networks and three-dimensional (3D) fracture networks is investigated. Finally, the potential applications to engineering are discussed, and potential open questions that may be useful for future works are provided.