Coupling Rock-Fracture Propagation with Thermal Stress and Fluid Flow
Publication: International Journal of Geomechanics
Volume 13, Issue 6
Abstract
This paper describes the theory behind a recent extension of a two-dimensional (2D) boundary-element code, FRACOD, to enable simulations of either coupled fracture (F)-hydraulic (H) processes or coupled F-thermal stress (T) in rocks. This extension is the next step in the ongoing development of a three-dimensional (3D) fracture mechanics code that couples F-H-T processes and predicts fracture initiation and propagation under thermal and hydraulic loadings. The original FRACOD simulated both mode I (tensile) and mode II (shear) fracture propagation that only involved mechanical processes in rock masses. In this study, the F-T coupling in FRACOD was developed using an indirect boundary-element method based on fictitious heat sources. The F-H coupling in FRACOD focused on fluid flow in explicit rock fractures using a cubic law. An explicit iteration method is used to simulate the fluid flow process in fractures and its interaction with mechanical deformation. Several verification and application cases have been included in the paper that demonstrate the effectiveness of the coupled functions. The extended code has been applied to the liquefied natural gas (LNG) underground storage experiment in South Korea and the Äspö pillar stability experiment (APSE) pillar spalling experiment in Sweden, and these applications are reported elsewhere.
Get full access to this article
View all available purchase options and get full access to this article.
References
Barton, N. (2007). Rock quality, seismic velocity, attenuation and anisotropy, Taylor & Francis, London.
Crouch, S. L., and Starfield, A. M. (1983). Boundary element methods in solid mechanics, George Allen & Unwin, London.
FRACOM. (2002). “A fracture propagation code – FRACOD.” User’s manual version 2.0., Helsinki, Finland.
Ghassemi, A., and Zhang, Q. (2004). “A transient fictitious stress boundary element method for porothermoelastic media.” Eng. Anal. Bound. Elem., 28(11), 1363–1373.
Guo, H., Aziz, N. I., and Schmidt, L. C. (1990). “Linear elastic crack tip modeling by the displacement discontinuity method.” Int. J. Numer. Methods Eng., 33(6), 919–942.
UDEC 4.0 [Computer software]. Minneapolis, Itasca Consulting.
Jing, L. (2003). “A review of techniques, advances and outstanding issues in numerical modeling for rock mechanics and rock engineering.” Int. J. Rock Mech. Min. Sci., 40(3), 283–353.
Klee, G., Bunger, A., Meyer, G., Rummel, F., and Shen, B. (2011). “In situ stresses in borehole blanche-1/south Australia derived from breakouts, core discing and hydraulic fracturing to 2 km depth.” Rock Mech. Rock Eng., 44(5), 531–540.
Min, K. B., Rutqvist, J., Tsang, C. F., and Jing, L. (2005). “Thermally induced mechanical and permeability changes around a nuclear waste repository—A far-field study based on equivalent properties determined by a discrete approach.” Int. J. Rock Mech. Min. Sci., 42(5–6), 765–780.
Rinne, M. (2008). “Fracture mechanics and subcritical crack growth approach to model time-dependent failure in brittle rock.” Doctoral dissertation, Helsinki Univ. of Technology, Helsinki, Finland.
Rinne, M., Shen, B., and Backers, T. (2012). “Modelling fracture propagation and failure in a rock pillar under mechanical and thermal loading.” J. Rock Mech. Geotech. Eng., 5(1), 73–83.
Rinne, M., Shen, B., Lee, H. S., and Jing, L. (2003). “Thermo-mechanical simulations of pillar spalling in SKB APSE test by FRACOD.” Int. Conf. on Coupled T-H-M-C Processes in Geo-systems: Fundamentals, Modelling, Experiments & Applications. O. Stephansson and J. A. Hudson, eds., Royal Institute of Technology, Stockholm, Sweden, 421–426.
Rutqvist, J., et al. (2005). “Numerical study of the THM effects on the near-field safety of a hypothetical nuclear waste repository – BMT1 of the DECOVALEX III project. Part 3: Effects of THM coupling in fractured rock.” Int. J. Rock Mech. Min. Sci., 42(5–6), 745–755.
Shen, B. (1995). “The mechanism of fracture coalescence in compression - Experimental study and numerical simulation.” Eng. Fract. Mech., 51(1), 73–85.
Shen, B., et al. (2008). “Coupled thermal-fracture behaviour of rock: Laboratory tests and numerical code development.” CSIRO Exploration and Mining Rep. P2008/2677, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Brisbane, Australia.
Shen, B., et al. (2011). “FRACOD modeling of rock fracturing and permeability change in excavation damaged zones.” Int. J. Geomech., 11(4), 302–313.
Shen, B., and Stephansson, O. (1994). “Modification of the G-criterion of crack propagation in compression.” Eng. Fract. Mech., 47(2), 177–189.
Shen, B., Stephansson, O., and Rinne, M. (2002). “Simulation of borehole breakouts using FRACOD 2D.” Oil Gas Sci. Technol., 57(5), 579–590.
Stephansson, O., et al. (2003). “Geomechanical evaluation and analysis of research shafts and galleries in MIU Project, Japan.” 1st Kyoto Int. Symp. on Underground Environment, Balkema, Rotterdam, Netherlands, 39–49.
Tan, X. C., Kou, S. Q., and Lindqvist, P. A. (1998). “Application of the DDM and fracture mechanics model on the simulation of rock breakage by mechanical tools.” Eng. Geol., 49(3–4), 277–284.
Timoshenko, S. P., and Goodier, J. N. (1970). Theory of elasticity, 3rd Ed., McGraw-Hill, New York.
Tsang, C.-F., Jing, L., Stephansson, O., and Kautsky, F. (2005). “The DECOVALEX III Project: A summary of activities and lessons learned.” Int. J. Rock Mech. Min. Sci., 42(5–6), 593–612.
Zhang, Q. (2004). “A boundary element method for thermo-poroelasticity with applications in rock mechanics.” M.Sc. thesis, Univ. of North Dakota, Grand Forks, ND.
Zhang, X., Jeffrey, R. G., and Detournay, E. (2005). “Propagation of a fluid-driven fracture parallel to the free surface of an elastic half plane.” Int. J. Numer. Anal. Methods Geomech., 29(13), 1317–1340.
Information & Authors
Information
Published In
International Journal of Geomechanics
Volume 13 • Issue 6 • December 2013
Pages: 794 - 808
Copyright
© 2013 American Society of Civil Engineers.
History
Received: May 11, 2012
Accepted: Dec 4, 2012
Published online: Dec 6, 2012
Published in print: Dec 1, 2013
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.