Balideh, S, Hilchey, A, Gilman, T & Kruse, S 2023, 'What happened to the structural model? A review of current open pit design practices and the development of structural models', in PM Dight (ed.), SSIM 2023: Third International Slope Stability in Mining Conference
, Australian Centre for Geomechanics, Perth, pp. 409-420, https://doi.org/10.36487/ACG_repo/2335_25
In open pit mining, major geologic structures (faults and shear zones) play a significant role in slope stability assessment and open pit design. Commonly, however, open pits at the pre-feasibility, feasibility and development levels lack a structural fault model at an appropriate scale. The scale and confidence of the structural model, as well as the experience of the development team to perform field work, review drillcore, interpret data and build the model, is vital to the structural sub-model portion of the geotechnical model. Herein, we briefly review metadata from a series of publicly available pre-feasibility to feasibility-level open pit design reports and provide comments on the development and confidence of those models, if present.
We then present the methods used to develop a major structure model at the scale of an open pit development. This methodology includes a review of available data sources, a structural analysis, a model development and a confidence rating methodology. The methodology is also illustrated with a case history.
Keywords: slope stability, structural model, open pit mining, confidence level, uncertainty, design stages
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