Authors: Mercier-Langevin, F; Wilson, D

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Mercier-Langevin, F & Wilson, D 2013, 'Lapa Mine – ground control practices in extreme squeezing ground', in Y Potvin & B Brady (eds), Proceedings of the Seventh International Symposium on Ground Support in Mining and Underground Construction, Australian Centre for Geomechanics, Perth, pp. 119-131.

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Many underground hard rock mines have to deal with various degrees of squeezing in underground tunnels. Depending on the severity of the phenomenon, considerable investments either in rock reinforcement and support can be necessary. In worst cases, time-consuming and possibly hazardous scaling and rehabilitation operations can be required to keep drifts serviceable. Therefore, a proper understanding of the rock mass, its response to excavation and the mechanisms involved is paramount to the design of cost-effective ground support systems in squeezing ground. The Lapa gold mine located in northwestern Quebec operates in such challenging ground conditions. Using field observations and data from the Hard Rock Squeezing Ground Index (Mercier-Langevin and Hadjigeorgiou, 2011), a plausible failure mechanism is proposed. The resulting ground control strategy is presented.

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