Saunders, E, LeRiche, A, Shapka-Fels, T & Barnett, W 2020, 'Characterisation of foliated rock masses using implicit modelling
to guide geotechnical domaining and slope design', 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. 535-550, https://doi.org/10.36487/ACG_repo/2025_32
The stability of rock slopes designed and excavated within anisotropic rock masses are influenced by several factors, some of which include spacing intensity, continuity, roughness, dip and dip direction, and waviness. Foliation-parallel instabilities are often expressed at the multi-bench or inter-ramp scale due to the high persistence, larger-scale dilation and breaking of intact rock bridges. Functional pit slope designs need to account for the variability in foliation character with consideration to the mining geometries being developed.
The accepted approach is to partition the rock mass into three-dimensional (3D) geotechnical domains to reduce complexity for slope design guidelines. Inputs guiding the development of the geotechnical domains can either be from highly manual interpretations, which are tedious and coarse in resolution, or implicit 3D foliation modelling methods. To demonstrate this, implicit models, such as form interpolants and/or block models, were first used at Jwaneng mine and have subsequently been generated and used to inform domaining and design at two operating mines (Rainy River and Rosebel Gold mines) and one other project site. The models were developed from different sources of geotechnical/geological data (i.e. oriented drillhole logging, televiewer, grade cutoff, pit face and photogrammetry mapping). The validation of the models has been further investigated with techniques presented in this paper.
Keywords: rock mass fabric, kinematics, geotechnical risk, pit design, bench performance, implicit modelling
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