Sainsbury, DP & Sainsbury, B 2013, 'Three-dimensional analysis of pit slope stability in anisotropic rock masses', in PM Dight (ed.), Slope Stability 2013: Proceedings of the 2013 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering
, Australian Centre for Geomechanics, Perth, pp. 683-695, https://doi.org/10.36487/ACG_rep/1308_45_Sainsbury
Anisotropic and foliated rock masses, the behaviour of which are dominated by closely spaced planes of weakness, present particular difficulties in the assessment of pit slope stability. Various numerical modelling techniques are available that explicitly simulate the joints and discontinuities within an anisotropic rock mass. However, due to the computational intensity of these numerical techniques, it is not practical to explicitly simulate the joint fabric of an entire three-dimensional pit slope for routine stability assessment. In order to simulate the effects of anisotropic rock mass strength and deformation behaviour on pit slope stability, a modelling methodology has been developed to account for rock mass anisotropy and scale effects using a continuum based ubiquitous joint constitutive model. This paper outlines the anisotropic modelling methodology and presents a series of demonstration models that have been used to validate the technique.
Al-Harthi, A.A. (1998) Effect of planar structures on the anisotropy of Ranyah sandstone, Saudi Arabia. Engineering Geology, Vol. 50, pp. 49–57.
Board, M., Chacon, E., Varona, P. and Lorig, L. (1996) Comparative Analysis of Toppling Behaviour at Chuquicamata Open-Pit Mine, Chile, Transactions Institute of Mining and Metallurgy, Vol. 105(a), January–April 1996, pp. A11–A21.
Brady, B.H.G and Brown, E.T. (2004) Rock Mechanics for Underground Mining, 3rd Edition, Springer, 614 p.
Brown, E.T., Richards, L.R. and Barr, M.V. (1977) Shear strength characteristics of delabole slates, in Proceedings Conference on Rock Engineering, P.B. Attewell (ed), University of Newcastle upon Tyne, UK, pp. 33–51.
Cai, M., Kaiser, P.K., Tasaka, Y. and Minami, M. (2007) Determination of residual strength parameters of jointed rock masses using the GSI system, International Journal of Rock Mechanics and Mining Sciences, Vol. 44, pp. 247–265.
Clark, I. (2006) Simulation of rock mass strength using ubiquitous-joints, Numerical Modeling in Geomechanics – 2006, in Proceedings 4th International FLAC Symposium, R. Hart and P. Verona (eds), 29–31 May 2006, Madrid, Spain, Itasca, Minneapolis, pp. 07–08.
Cundall, P.A. and Fairhurst, C. (1986) Correlation of discontinuum models with physical observations – an approach to the estimation of rock mass behaviour, Felsbau 4, No. 4, pp. 197–202.
Donath, F.A. (1972) Effects of cohesion and granularity on deformational behaviour of anisotropic rock, Studies in Mineralogy and Precambrain Geology, Geological Society of America Memoirs, Vol. 135, pp. 95–128.
Hoek, E. and Brown, E.T. (1980) Underground Excavations in Rock, London, Institution of Mining and Metallurgy, 527 p.
Itasca (2012) FLAC3D, Fast Lagrangian Analysis of Continua in Three-Dimensions, Itasca, Minneapolis, Version 5.0,
Itasca (2011) UDEC, Universal Distinct Element Code, Version 5.0, Itasca, Minneapolis,
Itasca (2007) 3-Dimensional Distinct Element Code, Version 4.0,
Jaeger, J.C. (1960) Shear failure of anisotropic rocks, Geological Magazine, Vol. 97, pp. 65–72.
Kale, S.M. and Trudinger, J.P. (1975) Slope stability investigations at the Mt Whaleback iron ore mine, Western Australia, in Proceedings SA Conference 1975, June 1975, The Australasian Institute of Mining and Metallurgy, Part B: Whyalla, Leigh Creek, and Adelaide, pp. 571–583.
Leitner, R., Potsch, M. and Schubert, W. (2006) Aspects on the Numerical Modeling of Rock Mass Anisotropy in Tunneling, Felsbau 24, No. 2, pp. 59–65.
McLamore, R. and Gray, K.E. (1967) The mechanical behaviour of anisotropic sedimentary rocks, Journal of Energy for Industry, Transactions of the American Society of Mechanical Engineers, Ser. B, Vol. 89, pp. 62–73.
RocScience (2013) SWEDGE Version 5.0, Toronto, Canada,
Sainsbury, B., Pierce, M. and Mas Ivars, D. (2008) Analysis of Caving Behaviour Using a Synthetic Rock Mass – Ubiquitous-joint Rock Mass Modelling Technique, in Proceedings First Southern Hemisphere International Rock Mechanics Symposium (SHIRMS), Y. Potvin, J. Carter, A. Dyskin and R. Jeffrey (eds), Vol. 1 – Mining and Civil, 16‒19 September 2008, Perth, Australia, Australian Centre for Geomechanics, Perth, pp. 243–523.
Sainsbury, D. and Sainsbury, B. (2013) Practical use of the Ubiquitous-Joint constitutive model for the simulation of anisotropic rock masses, in Proceedings 3rd International FLAC/DEM Symposium, M. Nelson (ed), 22–24 October 2013, Hangzhou, China, Itasca, Minneapolis (submitted).
Salcedo, D.A. (1983) Macizos Rocosos: Caracterización, Resistencia al Corte y Mecanismos de Rotura, in Proceedings 25 Aniversario Conferencia Soc. Venezolana de Mecánica del Suelo e Ingeniería de Fundaciones, Caracas, pp. 143–172.
Singh, J., Ramamurth, T. and Venkatappa, R.G. (1989) Strength anisotropies in rocks, Indian Geotechnical Journal, Vol. 19(2), pp. 147–166.
Tien, Y.M., Kuo, M.C and Juang, C.H. (2006) An experimental investigation of the failure mechanism of simulated transversely isotropic rocks, International Journal of Rock Mechanics and Mining Sciences, Vol. 43, pp. 1163–1181.
Yoshinaka, R., Osada, M., Park, H., Sasaki, T. and Sasaki, K. (2008) Practical determination of mechanical design parameters of intact rock considering scale effect, Engineering Geology, Vol. 96, pp. 173–186.