Authors: Naidoo, K; Handley, MF; Leach, AP


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Naidoo, K, Handley, MF & Leach, AP 2008, 'Applying Numerical Modelling to Pillar Design in South African Mines — An Initial Study', in Y Potvin, J Carter, A Dyskin & R Jeffrey (eds), SHIRMS 2008: Proceedings of the First Southern Hemisphere International Rock Mechanics Symposium, Australian Centre for Geomechanics, Perth, pp. 379-390,

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The use of bord and pillar mining methods is a favoured approach to mining in many shallow tabular mines, where the orebody dip is relatively flat. Although much work has been done on design methods for pillars under various rock mass conditions, there seems to be a lack of consensus in terms of a uniform methodology that should be used throughout the mining industry. Moreover, there is no synergy between the coal, hard rock gold and platinum mines and the iron ore and manganese mines that use this method of mining. The purpose of this paper is to present the results of a preliminary analysis that is being carried out to try and find the ‘Holy Grail’ in the form of a generalised pillar design criterion or formula that is applicable to all mining environments and all modes of failure. Numerical modelling has been performed to ascertain the mechanism of failure in a range of cases and the effect that changes in pillar dimension may have had on pillar stability. At this time only square pillars have been considered.

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