This paper presents a systematic research for understanding mechanical shearing effects on the fluid flow and the solute transport behavior of rough fractures through a numerical simulation approach. The aperture fields were modeled based on a real rock fracture geometry and the normal displacement obtained from the shear-flow test. The fluid flow through the rough fracture under shear was simulated using a finite element code that solves the Reynolds equation, and the transport behavior through the rough fracture under shear was simulated calculating the advection–dispersion equation. The results show that the fracture apertures increase as the shear displacement increases, with a few major flow channels detected through the fracture. The shear-induced flow channels increase both flow connectivity and transport connectivity, which accelerate the movement of solutes in a particular direction and lead to early breakthrough of the contaminants. Adsorption, acting as a retardation term, has a decisive influence on the transport process. These results can give a basic knowledge of the hydromechanical and solute transport progress through fracture, and will be helpful to safety assessment for high-level radioactive waste disposal facilities.

Accepted:

Published online:

Yubao Zhang ^{1};
Na Huang ^{2, 3}

@article{CRMECA_2018__346_9_877_0, author = {Yubao Zhang and Na Huang}, title = {Numerical study on the shear-flow behavior and transport process in rough rock fractures}, journal = {Comptes Rendus. M\'ecanique}, pages = {877--886}, publisher = {Elsevier}, volume = {346}, number = {9}, year = {2018}, doi = {10.1016/j.crme.2018.05.006}, language = {en}, }

Yubao Zhang; Na Huang. Numerical study on the shear-flow behavior and transport process in rough rock fractures. Comptes Rendus. Mécanique, Volume 346 (2018) no. 9, pp. 877-886. doi : 10.1016/j.crme.2018.05.006. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/j.crme.2018.05.006/

[1] Effective hydraulic conductivity of fractured clay beds at a hazardous waste landfill, Louisiana Gulf Coast, Water Resour. Res., Volume 29 (1993) no. 11, pp. 3691-3698

[2] Geohydromechanical processes in the Excavation Damaged Zone in crystalline rock, rock salt, and indurated and plastic clays—in the context of radioactive waste disposal, Int. J. Rock Mech. Min. Sci., Volume 42 (2005) no. 1, pp. 109-125

[3] Introduction to the Numerical Modeling of Groundwater and Geothermal Systems: Fundamentals of Mass, Energy and Solute Transport in Poroelastic Rocks, CRC Press, Boca Raton, FL, USA, 2010

[4] et al. Some anomalous features of flow and solute transport arising from fracture aperture variability, Water Resour. Res., Volume 26 (1990) no. 10, pp. 2377-2391

[5] et al. A numerical approach for assessing effects of shear on equivalent permeability and nonlinear flow characteristics of 2-D fracture networks, Adv. Water Resour., Volume 111 (2018), pp. 289-300

[6] et al. Effects of fracture surface roughness and shear displacement on geometrical and hydraulic properties of three-dimensional crossed rock fracture models, Adv. Water Resour., Volume 113 (2018), pp. 30-41

[7] Elastoplastic coupling solution of circular openings in strain-softening rock mass considering pressure-dependent effect, Int. J. Geomech., Volume 18 (2018) no. 1

[8] et al. Fractal characterization of dynamic fracture network extension in porous media, Fractals, Volume 25 (2017) no. 02

[9] Geometrical, fractal and hydraulic properties of fractured reservoirs: a mini-review, Adv. Geo-energ. Res., Volume 1 (2017) no. 1, pp. 31-38

[10] Influences of hydraulic gradient, surface roughness, intersecting angle, and scale effect on nonlinear flow behavior at single fracture intersections, J. Hydrol., Volume 538 (2016), pp. 440-453

[11] Critical hydraulic gradient for nonlinear flow through rock fracture networks: the roles of aperture, surface roughness, and number of intersections, Adv. Water Resour., Volume 88 (2016), pp. 53-65

[12] A fractal model based on a new governing equation of fluid flow in fractures for characterizing hydraulic properties of rock fracture networks, Comput. Geotech., Volume 75 (2016), pp. 57-68

[13] Hydraulic characteristics of single rough fracture under shear deformation, EUROCK 2005 (2005)

[14] Development of a shear-flow test apparatus and determination of coupled properties for a single rock joint, Int. J. Rock Mech. Min. Sci., Volume 36 (1999) no. 5, pp. 641-650

[15] An experimental investigation of hydraulic behaviour of fractures and joints in granitic rock, Int. J. Rock Mech. Min. Sci., Volume 37 (2000) no. 7, pp. 1061-1071

[16] Effect of shear displacement on the aperture and permeability of a rock fracture, Int. J. Rock Mech. Min. Sci., Volume 35 (1998) no. 8, pp. 1051-1070

[17] Size effect on aperture and permeability of a fracture as estimated in large synthetic fractures, Int. J. Rock Mech. Min. Sci., Volume 43 (2006) no. 5, pp. 726-755

[18] A fractal model for characterizing fluid flow in fractured rock masses based on randomly distributed rock fracture networks, Comput. Geotech., Volume 65 (2015), pp. 45-55

[19] Numerical study of the geometrical and hydraulic characteristics of 3D self-affine rough fractures during shear, J. Nat. Gas Sci. Eng., Volume 45 (2017), pp. 127-142

[20] et al. A predictive model of permeability for fractal-based rough rock fractures during shear, Fractals, Volume 25 (2017) no. 05

[21] Numerical modelling of fluid flow tests in a rock fracture with a special algorithm for contact areas, Comput. Geotech., Volume 36 (2009) no. 1, pp. 291-303

[22] Solute transport in a single fracture with negligible matrix permeability: 1. Fundamental mechanisms, Hydrogeol. J., Volume 11 (2003) no. 4, pp. 418-433

[23] Flow and tracer transport in a single fracture: a stochastic model and its relation to some field observations, Water Resour. Res., Volume 24 (1988) no. 12, pp. 2033-2048

[24] Effect of fracture aperture variations on the dispersion of contaminants, Water Resour. Res., Volume 35 (1999) no. 1, pp. 55-63

[25] Solute transport in variable-aperture fractures: an investigation of the relative importance of Taylor dispersion and macrodispersion, Water Resour. Res., Volume 36 (2000) no. 7, pp. 1611-1625

[26] Transport simulation with stochastic aperture for a single fracture–comparison with a laboratory experiment, Adv. Water Resour., Volume 25 (2002) no. 1, pp. 19-32

[27] Diffusion in the rock matrix: an important factor in radionuclide retardation, J. Geophys. Res., Solid Earth, Volume 85 (1980) no. B8, pp. 4379-4397

[28] Contaminant transport in one-dimensional single fractured media: semi-analytical solution for three-member decay chain with pulse and Heaviside input sources, Hydrol. Process., Volume 21 (2007) no. 16, pp. 2135-2143

[29] Experimental and numerical study of the geometrical and hydraulic characteristics of a single rock fracture during shear, Int. J. Rock Mech. Min. Sci., Volume 48 (2011) no. 8, pp. 1292-1302

[30] Joint conductivity variation due to normal and shear deformation, Proceedings of the International Symposium on Rock Joints, Loen, Norway, Balkema, Rotterdam, 1990, pp. 535-540

[31] Numerical simulations for the effects of normal loading on particle transport in rock fractures during shear, Int. J. Rock Mech. Min. Sci., Volume 45 (2008) no. 8, pp. 1403-1419

[32] et al. Validity of cubic law for fluid flow in a deformable rock fracture, Water Resour. Res., Volume 16 (1980) no. 6, pp. 1016-1024

[33] et al. A numerical method for simulating fluid flow through 3-D fracture networks, J. Nat. Gas Sci. Eng., Volume 33 (2016), pp. 1271-1281

[34] Evaluation of hydrodynamic dispersion parameters in fractured rocks, J. Rock Mech. Geotech. Eng., Volume 2 (2010) no. 3, pp. 243-254

[35] Flux-averaged and volume-averaged concentrations in continuum approaches to solute transport, Water Resour. Res., Volume 20 (1984) no. 7, pp. 866-872

[36] Numerical simulation of solute transport in rough fractures, J. Geophys. Res., Solid Earth, Volume 96 (1991) no. B3, pp. 4157-4166

[37] Flow and tracer transport in fractured media: a variable aperture channel model and its properties, Water Resour. Res., Volume 24 (1988) no. 12, pp. 2049-2060

[38] Shear-induced flow channels in a single rock fracture and their effect on solute transport, Transp. Porous Media, Volume 87 (2011) no. 2, pp. 503-523

[39] Channel model of flow through fractured media, Water Resour. Res., Volume 23 (1987) no. 3, pp. 467-479

[40] Tracer movement in a single fracture in granitic rock: some experimental results and their interpretation, Water Resour. Res., Volume 18 (1982) no. 4, pp. 849-858

[41] Analysis of laboratory tracer runs in natural fissures, Water Resour. Res., Volume 21 (1985) no. 7, pp. 951-958

*Cited by Sources: *

Comments - Policy