Li, J 2020, 'Elimination of structure controlled highwall failures at an open cut coal mine', in PM Dight (ed.), Slope Stability 2020: Proceedings of the 2020 International Symposium on Slope Stability in Open Pit Mining and Civil Engineering
, Australian Centre for Geomechanics, Perth, pp. 1373-1382, https://doi.org/10.36487/ACG_repo/2025_94
Open cut coal mines, particularly fresh rock masses of open cut coal mines, experience few large highwall failures unless one or more unfavourable geological structures daylight. A number of challenges exist for identifying, analysis and operationally controlling the failure risk. The first challenge is to obtain accurate fault models (or planes) from traditional exploration by drill holes, until the geological structures are exposed on a highwall face and a coal seam roof. The second challenge is to acquire rock mass strengths and then to use process to assess the stability of the potential structure controlled failure. The third is to propose a most effective strategy to eliminate or control the potential large structure during pit design to coal uncovering stages, as soon as the fault structure plane becomes available. Consequently, the coal along the riskeliminated area can be mined the safely to design. This paper presents details of confronting these challenges and examples of proactively managing highwall failure risks at a Bowen Basin open cut coal mine in Queensland, Australia.
Keywords: open cut coal mine, geological structure, highwall, failure elimination
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