... time ventilation shaft excavation shotcrete shaft probability wedge formation tunnel borehole 01 AfriRock 2017 Rock Mechanics for Africa Cape Town, 2 7 October 2017 The Southern African Institute of Mining and Metallurgy 427 An empirical and numerical approach to quantifying raisebore-hole...

... probability of planar and wedge failure at set of benches. Safety factors for overall slope indicate planar failure of profile B, although stable, remains below the acceptance criteria for the overall slope angle, which opted for numerical analysis. Profile C was deemed stable and no further analyses were...

... extraction, but rather the predicted rock mass and pillar behaviour prior to pillar extraction. metals & mining criterion stability probability representative area pillar strength square cut pillar solid pillar mining height extraction ratio safety factor single diagonal cut Snook...