Modern geomechanical assessment of influence of rockbursts in tectonic areas on mine stability in the North Urals Bauxite Mine

Abstract

Experience of the North Urals Bauxite Mine shows that the current conditions, namely, mining technologies and rates per extraction panels, as well some other geotechnical factors not always and not in full conform with the actual geology and geomechanics, which affects mining safety. VNIMI accomplished the research aimed at efficiency evaluation of room-and-pillar mining in complicated geodynamic conditions of the North Urals Bauxite Mine. It is found that stability of mine support elements is greatly affected by additional dynamic load induced by deformation of block rock mass. Mining-initiated reactivation of healed faults leads to liberation of large amounts of accumulated energy, which results in dynamic failures in mines. The quantitative estimation of such energy was carried out using Russian software PRESS 3D URAL. The computer modeling results point at the additional concentration of dynamic stresses during slippage along the healed faults, which should be taken into account in mine support design. Before and during actual stoping in extraction panels, it is required to implement geodynamic zoning to update the local tectonic structure, as well as the anticipatory computer-aided prediction (using the adapted anticipatory computerized simulation in PRESS 3D URAL) of the stress–strain behavior and geodynamic safety of rock mass with regard to the widely varying geological factors, their complication with growing depth, as well as aggravation of geodynamic regime and rockburst hazard.