Pierce, M, Weatherley, DK & Kojovic, T 2010, 'A hybrid methodology for secondary fragmentation prediction in cave mines', in Y Potvin (ed.), Proceedings of the Second International Symposium on Block and Sublevel Caving
, Australian Centre for Geomechanics, Perth, pp. 567-581.
Drawing upon numerical studies, published laboratory results and comminution theory, a new methodology has been developed for the prediction of drawpoint size distributions throughout the operational life of a cave mine. The method is ‘hybrid’ because it utilises both numerical modelling and empirical comminution relations to track the evolution of caved rock size distributions reporting at drawpoints. In this paper we review the current knowledge on caved rock fragmentation, present new results analysing the micromechanics of shear-induced attrition of granular materials, and demonstrate via back-analysis, the applicability of the hybrid methodology for predicting drawpoint fragment size-distributions in existing caving operations.
Bridgwater, J., Utsumi, R., Zhang, Z. and Tuladhar, T. (2003) Particle attrition due to shearing – the effects of stress, strain and particle shape, Chemical Engineering Science, Vol. 58, pp. 4649–4665.
Brown, E.T. (2003) Block Caving Geomechanics (The International Caving Study I, 1997–2000) University of Queensland, JKMRC Monograph Series in Mining and Mineral Processing 3, Indooroopilly, Australia.
Castro, R. (2006) Study of the mechanisms of granular flow for block caving, PhD thesis, University of Queensland, Australia.
Coop, M.R., Sorensen, K.K, Bodas Freitas, T. and Georgoutsos, G. (2004) Particle breakage during shearing of a carbonate sand, Geotechnique, Vol. 54, No. 3, pp. 157–163.
Esterhuizen, G.S. (1999) A Program to Predict Block Cave Fragmentation, Technical Reference and User’s Guide, Version 3.0.
Esterhuizen, G.S. (1998) ICS Meeting Minutes, BCF Review, Brisbane, Australia.
Esterle, J.S., O’Brien, G.O., Thornton, D., Kojovic, T. and Firth, B. (1998) Tracking coal fragmentation from pit face top plant feed, Mine to Mill 1998 Conference, Brisbane, Australia, pp. 165–169.
Fukumoto, T. (1992) Particle breakage characteristics in granular soils, Soils Foundations, Vol. 32, No. 1, pp. 26–40.
Ghadiri, M., Ning, Z., Kenter, S.J. and Puik, E. (2000) Attrition of granular solids in a shear cell, Chemical Engineering Science, Vol. 55, pp. 5445–5456.
Hardin, B.O. (1985) Crushing of soil particles, Journal of Geotechnical, Engineering ASCE, Vol. 111(10),
Hoek, E. and Brown, E.T. (1980) Underground Excavations, In Rock, London, Institution of Mining and Metallurgy.
Lade, P.V. and Yamamuro, J.A. (1996) Undrained sand behavior in axisymmetric tests at high pressures, Journal of Geotechnical Engineering, ASCE, Vol. 122(2), pp. 120–129.
Laubscher, D.H. (2000) Block Caving Manual, prepared for International Caving Study, JKMRC and Itasca Consulting Group Inc., Brisbane, Australia.
Lee, D.M. (1992) The angles of friction of granular fills, PhD dissertation, University of Cambridge.
Lee, K.J. and Farhoomand, I. (1967) Compressibility and crushing of granular soils in anisotropic triaxial compression, Canadian Geotechnical Journal, Ottawa, Canada, Vol. 4(1), pp. 68–86.
Lorig, L.J. and Cundall, P.A. (2000) A rapid gravity flow simulator, Final Report, International Caving Study, E.T. Brown (ed), JKMRC and Itasca Consulting Group Inc., Brisbane, Australia.
Marsal, R.J. (1967) Large scale testing of rockfill materials, Journal of Soil Mecanics and Foundations Division, ASCE, Vol. 93(2), pp. 27–43.
McDowell, G.R. (2005) A physical justification for log e – log s based on fractal crushing and particle kinematics, Geotechnique, Vol. 55(9), pp. 697–698.
McDowell, G.R. and Bolton, M.D. (1998) On the micromechanics of crushable aggregates, Geotechnique, Vol. 48(5), pp. 667–679.
McDowell, G.R., Bolton, M.D. and Robertson, D. (1996) The fractal crushing of granular materials, Journal of the Mechanics and Physics of Solids, Vol. 44(12), pp. 2079–2102.
McKee, D.J. and Kojovic, T. (1997) Comminution in a mining context, in Proceedings SME’97 Comminution Practices Conference, Denver, Colorado, pp. 271–278.
Nakata, Y., Hyodo, M., Hyde, A.F.L., Kato, Y. and Murata, H. (2001) Microscopic particle crushing and sand subjected to one-dimensional compression, Soils and Foundations, Japanese Geotechnical Society, Vol. 41(1), pp. 69–82.
Napier-Munn, T.J., Morrell, S., Morrison, R.D. and Kojovic, T. (1996) Mineral Comminution Circuits: Their Design and Optimisation, JKMRC, University of Queensland, Brisbane, 413 p.
Paramanathan, B.K. and Bridgwater, J. (1983) Attrition of solids—II: Material behaviour and the kinetics of attrition, Chemical Engineering Science, Vol. 38, pp. 207–224.
Pierce, M.E. (2004) Final Report, International Caving Study II, JKMRC and Itasca Consulting Group Inc., Brisbane, Australia.
Pierce, M.E. (2007) Six Monthly Technical Report, Gravity Flow Mechanics and SLC Blasting and Flow, Sub-Project No. 1.2 and 3.2.3: REBOP Development and Disturbed Flow Modelling, Itasca Consulting Group Inc., Report to Mass Mining Technology Project, 2004–2007, ICG06-2292-13-Tasks 1 and 9, March.
Pierce, M., Cundall, P., Mas Ivars, D., Darcel, C., Young, R.P., Reyes-Montes, J. and Pettitt, W. (2006) Six Monthly Technical Report, Caving Mechanics, Sub-Project No. 4.2: Research and Methodology Improvement, and Sub-Project 4.3, Case Study Application, Itasca Consulting Group, Inc., Report to Mass Mining Technology Project, 2004-2007, ICG06-2292-1-Tasks-2-3-14, March.
Rumpf, H. (1973) Physical aspects of comminution and a new formulation of a Law of Comminution, Powder Technology, Vol. 7, pp. 145–159.
Shi, F. and Kojovic, T. (2007) Validation of a Model for Impact Breakage Incorporating Particle Size Effect, International Journal of Mineral Processing, Vol. 82, pp. 156–163.
Turcotte, D.L. (1986) Fractals and fragmentation, Journal of Geophysical Research, Vol. 91(B2), pp. 1921–1926.
Vogel, L. and Peukert, W. (2003) Breakage behaviour of different materials – construction of a mastercurve for the breakage probability, Powder Technology, Vol. 129, pp. 101–110.
Vogel, L. and Peukert, W. (2004) Determination of material properties relevant to grinding by practicable labscale milling tests, International Journal of Minerals Processing, Vol. 74S, pp. 329–338.
Weibull, W. (1951) A statistical distribution function of wide applicability, Journal of Applied Mechanics, Vol. 9,
Yamamuro, J.A. and Lade, P.V. (1996) Drained sand behavior in axisymmetric tests at high pressures, Journal of Geotechnical Engineering, ASCE, Vol. 122(2), pp. 109–119.
Yamamuro, J.A., Bopp, P.A. and Lade, P.V. (1996) One-dimensional compression of sands at high pressures, Journal of Geotechnical Engineering, ASCE, Vol. 122(2), pp. 147–154.
Yamamuro, J.A. (1993) Instability and behaviour of granular materials at high pressures, PhD dissertation, Deptartment of Civil Engineering, University of California, Los Angeles.