DOI QR코드

DOI QR Code

Validation of 3D discrete fracture network model focusing on areal sampling methods-a case study on the powerhouse cavern of Rudbar Lorestan pumped storage power plant, Iran

  • Bandpey, Abbas Kamali (Department of Mining and Metallurgical Engineering, Amirkabir University of Technology) ;
  • Shahriar, Kourush (Department of Mining and Metallurgical Engineering, Amirkabir University of Technology) ;
  • Sharifzadeh, Mostafa (Department of Mining Engineering and Metallurgy Engineering, Western Australian School of Mines (WASM), Curtin University) ;
  • Marefvand, Parviz (Department of Mining and Metallurgical Engineering, Amirkabir University of Technology)
  • 투고 : 2017.04.20
  • 심사 : 2018.03.07
  • 발행 : 2018.09.20

초록

Discontinuities considerably affect the mechanical and hydraulic properties of rock mass. These properties of the rock mass are influenced by the geometry of the discontinuities to a great extent. This paper aims to render an account of the geometrical parameters of several discontinuity sets related to the surrounding rock mass of Rudbar Lorestan Pumped Storage Power Plant powerhouse cavern making use of the linear and areal (circular and rectangular) sampling methods. Taking into consideration quite a large quantity of scanline and the window samplings used in this research, it was realized that the areal sampling methods are more time consuming and cost-effective than the linear methods. Having corrected the biases of the geometrical properties of the discontinuities, density (areal and volumetric) as well as the linear, areal and volumetric intensity accompanied by the other properties related to four sets of discontinuities were computed. There is an acceptable difference among the mean trace lengths measured using two linear and areal methods for the two joint sets. A 3D discrete fracture network generation code (3DFAM) has been developed to model the fracture network based on the mapped data. The code has been validated on the basis of numerous geometrical characteristics computed by use of the linear, areal sampling methods and volumetric method. Results of the linear sampling method have significant variations. So, the areal and volumetric methods are more efficient than the linear method and they are more appropriate for validation of 3D DFN (Discrete Fracture Network) codes.

키워드

참고문헌

  1. Baghbanan, A. (2008), "Scale and stress effects on hydromechanical properties of fractured rock masses", Ph.D. Dissertation, KTH Royal Institute of Technology, Stockholm, Sweden.
  2. Brown, E.T. (1981), ISRM Suggested Methods: Rock Characterization, Testing and Monitoring, Pergamon Press, London, U.K.
  3. Dershowitz, S.D. and Herda, H.H. (1992), "Interpretation of fracture spacing and intensity", Proceedings of the 33rd US Symposium on Rock Mechanics, Santa Fe, New Mexico, U.S.A., June.
  4. Kamali, A., Shahriar, K., Sharifzadeh, M., Aalianvari, A. and Esmaeilzadeh, A. (2016), "Effect of shape and size of window sampling on the determination of average length, intensity and density of trace discontinuity", Proceedings of the Symposium on the Rock Mechanics and Rock Engineering, Cappadocia, Turkey, August.
  5. Kemeny, J. and Post, R. (2003), "Estimating three-dimensional rock discontinuity orientation from digital images of fracture traces", Comput. Geosci., 29(1), 65-77. https://doi.org/10.1016/S0098-3004(02)00106-1
  6. Kulatilake, P.H.S.W. and Wu, T.H. (1984), "Estimation of mean trace length of discontinuities", Rock Mech. Rock Eng., 17(4), 215-232. https://doi.org/10.1007/BF01032335
  7. Kulatilake, P.H.S.W., Wathugala, D.N. and Stephansson, O. (1993), "Joint network modeling with a validation exercise in Stripa Mine, Sweden", J. Rock Mech. Min. Sci. Geomech. Abstr., 30(5), 503-526. https://doi.org/10.1016/0148-9062(93)92217-E
  8. Kulatilake, P.H.S.W., Wathugala, D.N. Poulton, M. and Stephansson, O., (1990), "Analysis of structural homogeneity of rock masses", J. Eng. Geol., 29(3), 195-211. https://doi.org/10.1016/0013-7952(90)90050-B
  9. Li, Y., Chen, J. and Shang, Y. (2017), "Connectivity of threedimensional fracture networks: A case study from a dam site in southwest China", Rock Mech. Rock Eng., 50(1), 241-249. https://doi.org/10.1007/s00603-016-1062-5
  10. Mauldon, M, Rohrbaugh Jr., M.B., Dunne, W.M. and Lawdermilk, W. (1999), "Mean fracture trace length and density estimators using circular windows", Proceedings of the 37th U.S. Symposium on Rock Mechanics (USRMS), Vail, Colorado, U.S.A., June.
  11. Mauldon, M. (1998), "Estimating mean fracture Trace length and density from observations in convex window", J Rock Mech. Rock Eng., 31(4), 201-216. https://doi.org/10.1007/s006030050021
  12. Mauldon, M., Dunne W.M. and Rohrbaugh Jr., M.B. (2001), "Circular scanline and circular windows: New tools for characterizing the geometry of fracture traces", J. Struct. Geol., 23(2-3), 247-258. https://doi.org/10.1016/S0191-8141(00)00094-8
  13. Mauldon, M., Rohrbaugh Jr., M.B., Dunne, W.M. and Lawdermilk, W. (1999), "Fracture intensity estimates using circular scanlines", Proceedings of the 37th U.S. Symposium on Rock Mechanics (USRMS), Vail, Colorado, U.S.A., June.
  14. Ni, P., Wang, S., Wang, C. and Zhang, S. (2017), "Estimation of REV size for fractured rock mass based on damage coefficient", Rock Mech. Rock Eng., 50(3), 555-570. https://doi.org/10.1007/s00603-016-1122-x
  15. Noroozi, M., Kakaie, R. and Jalali, S.E. (2015), "3D geometricalstochastical modeling of rock mass joint networks: Case study of the right bank of Rudbar Lorestan Dam plant", J. Geol. Min. Res., 7(1), 1-10. https://doi.org/10.5897/JGMR14.0213
  16. Pallat, J. (2004), SPSS Survival Manual, Amazon Publisher Inc.
  17. Priest, S.D. (1993), Discontinuity Analysis for Rock Engineering, Chapman and Hall Press, London, U.K.
  18. Priest, S.D. and Hudson, J.A. (1981), "Estimation of discontinuity spacing and trace length using scanline surveys", J. Rock Mech. Min. Sci. Geomech. Abstr., 18(3), 183-197. https://doi.org/10.1016/0148-9062(81)90973-6
  19. Reeves, D.M., Parashar, R., Pohll, G., Carroll, R., Badger, T. and Willoughby, K. (2013), "The use of discrete facture network simulations in the design of horizontal hillslope drainage networks in fractured rock", J. Eng. Geol., 163, 132-143. https://doi.org/10.1016/j.enggeo.2013.05.013
  20. Rohrbaugh Jr., M.B., Dunne, W.M. and Mauldon, M. (2002), "Estimating fracture trace intensity, density and mean length using circular scanlines and windows", AAPG Bull., 86(12), 2089-2104.
  21. Wang, X. (2005), "Stereological interpretation of rock fracture traces on borehole walls and other cylindrical surfaces", Ph.D. Dissertation, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, U.S.A.
  22. Weiss, M. (2008), "Techniques for estimating fracture size: A comparison of methods, Technical note", J. Rock Mech. Min. Sci., 3(45), 460-466.
  23. Xu, C. and Dowd, P. (2010), "A new computer code for discrete fracture network modeling", Comput. Geosci., 36(3), 292-301. https://doi.org/10.1016/j.cageo.2009.05.012
  24. Yoon, S., Lee, S.R., Kim, Y.T. and Go, G.H. (2015), "Estimation of saturated hydraulic conductivity of Korean weathered granite soils using a regression analysis", Geomech. Eng., 9(1), 101-113 https://doi.org/10.12989/gae.2015.9.1.101
  25. Zeeb, C., Gomez-Rivas, E., Bons, P.D., Virgo, S. and Blum, P. (2013), "Fracture network evaluation program (FraNEP): A software for analyzing 2D fracture trace-line maps", J. Comput. Geosci., 60, 11-22. https://doi.org/10.1016/j.cageo.2013.04.027
  26. Zhang, L. and Ding, X. (2010), "Variance of non-parametric rock fracture mean trace length estimator", J. Rock Mech. Min. Sci., 7(47), 1222-1228.
  27. Zhang, L. and Einstein, H.H. (1998), "Estimating the mean trace length of rock discontinuities", Rock Mech. Rock Eng., 31(4), 217-235. https://doi.org/10.1007/s006030050022
  28. Zhang, L. and Einstein, H.H. (2000), "Estimating the intensity of rock discontinuities", J. Rock Mech. Min. Sci., 37(5), 819-837. https://doi.org/10.1016/S1365-1609(00)00022-8
  29. Zhang, Q.H. and Yin, J.M. (2014), "Solution of two key issues in arbitrary three-dimensional discrete fracture network flow models", J. Hydrol., 514, 281-296. https://doi.org/10.1016/j.jhydrol.2014.04.027
  30. Zhang, W., Chen, J., Cao, Z. and Wang, R. (2013), "Size effect of RQD and generalized representative volume elements: A case study on an underground excavation in Baihetan dam, Southwest China", Tunn. Undergr. Sp. Technol., 35, 89-98. https://doi.org/10.1016/j.tust.2012.12.007
  31. Zheng, J., Deng, J., Yang, X., Wei, J. Zheng, H. and Cui, Y. (2014), "An improved Monte Carlo simulation method for discontinuity orientations based on Fisher distribution and its program implementation", J. Comput. Geotech., 61, 266-276. https://doi.org/10.1016/j.compgeo.2014.06.006
  32. Zheng, J., Deng, J., Zhang, G. and Yang, X. (2015), "Validation of Mont Carlo simulation for discontinuity locations in space", J. Comput. Geotech., 67, 103-109. https://doi.org/10.1016/j.compgeo.2015.02.016
  33. Zimmerman, R.W. and Main, I. (2004), Hydromechanical Behavior of Fractured Rocks, in Mechanics of Fluid-saturated Rocks, Elsevier, 363-421.