Authors: Vallejos, JA; Miranda, R; Marambio, E; Burgos, L; Sanhueza, G

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Vallejos, JA, Miranda, R, Marambio, E, Burgos, L & Sanhueza, G 2020, 'Assisted geotechnical design for sublevel open stoping using MineRoc® software', in J Wesseloo (ed.), Proceedings of the Second International Conference on Underground Mining Technology, Australian Centre for Geomechanics, Perth, pp. 309-324,

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The prediction of rock mass stability in sublevel open stope (SLOS) mining is performed in the design of open stopes to estimate the stope size required to reduce operational hazards and achieve continuous production. For almost four decades, the Stability Graph method has been used for this purpose. Several improvements of the Stability Graph method have taken place through the years. However, there is still work to be done. Accordingly, new case studies need to be continuously collected in order to update the Stability Graph, improving its reliability in predicting the stability state of open stopes to a specific site condition. Two main stages are considered for the collection of new case studies. First, the required geotechnical data of a specific site condition is collected. Then, in the back-analysis of open stopes, performance parameters related with the geometry are calculated, and a stability state is assigned to each case study. When these stages are systematically performed, the Stability Graph can be calibrated, delineating more reliable new stability boundaries. However, some problems in the collection of new case studies in SLOS operations such as disorder in geotechnical data or miscalculation of performance parameters impede the correct improvement of the stability boundaries. To deal with these problems, several computational tools have been developed and integrated into the software MineRoc®. This paper shows a geotechnical analysis of a proposed open stope design through an updated version of MineRoc®, using Stability Graph boundaries previously defined. New features of the software and an application to a specific sublevel open stoping mine are presented, illustrating how MineRoc® positively impacts on the mine design and planning processes.

Keywords: sublevel stoping, Stability Graph method, geotechnical analysis, mine design, MineRoc, software

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