Authors: Karami, A; Greer, S; Beddoes, R


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Karami, A, Greer, S & Beddoes, R 2007, 'Numerical Assessment of Step-Path Failures of Northwest Wall of A154 Pit, Diavik Diamond Mines', in Y Potvin (ed.), Slope Stability 2007: Proceedings of the 2007 International Symposium on Rock Slope Stability in Open Pit Mining and Civil Engineering, Australian Centre for Geomechanics, Perth, pp. 293-305,

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The presence of intact rock bridges in the rock mass and their effect on the formation of step-path failure surface in pit slopes have been the subject of research in the last three decades beginning with the work of Jennings (1970). Step-path failure mechanism has been investigated more recently by rock mechanics engineers and consultants using advanced discontinuum numerical techniques. This paper reviews briefly the state of current application of step-path failure in practice and presents the results of one such investigation into the stability assessment of the northwest wall of A154 pit of Diavik Diamond Mine in Northwest Territories, Canada. Results of the numerical assessment are compared with those of limit equilibrium assessment and the importance of such investigations in practice, in particular in deep open pit mines where high stress conditions near the slope toe is present are discussed.

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