Authors: Louchnikov, V


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Louchnikov, V 2011, 'Simple calibration of the extension strain criterion for its use in numerical modelling', in Y Potvin (ed.), Strategic versus Tactical 2011: Proceedings of the Fourth International Seminar on Strategic versus Tactical Approaches in Mining, Australian Centre for Geomechanics, Perth, pp. 85-96,

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Calibrating numerical models is generally considered to be a rather time-consuming exercise which commonly involves a number of activities such as obtaining instrument readings, observing and mapping progressive rock mass damage, conducting various rock tests and surveying. While it is certainly absolutely necessary to undertake all these actions to make numerical models a working tool, quite often site personnel have no time or resources dedicated for a proper calibration process. In this paper, a simple technique of measuring fractures in drill holes around development drives and then relating the damage patterns to the extension strain contours modelled in a boundary element method (BEM) code is discussed. This technique has been used by the author at a number of operations and was found to be practically effective. A case study is presented where such calibration is shown to be instrumental in deciding on the optimal mining sequence in overstressed ground.

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