Authors: Ranasooriya, J; Nikraz, H

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Ranasooriya, J & Nikraz, H 2008, 'Tetrahedral Rock Wedge Stability Under Empirically Derived Support ', 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. 619-631,

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The support measures determined by rock mass rating (RMR) and Q rock mass classification methods were compared with a tetrahedral rock wedge stability analysis of the rock mass around two water conveyance tunnels. The study indicates that the support measures recommended by the two classification methods are generally adequate, but are insufficient to provide an adequate safety margin against some of the possible rock wedge failures under project specific conditions.

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