Parkes, J, Young, D, Jung, JD & Goldstein, D 2023, 'Rio Tinto Iron Ore mines actual failure percentages case study', in PM Dight (ed.), SSIM 2023: Third International Slope Stability in Mining Conference, Australian Centre for Geomechanics, Perth, pp. 105-114, https://doi.org/10.36487/ACG_repo/2335_04
(https://papers.acg.uwa.edu.au/p/2335_04_Parkes/)
Abstract: Rio Tinto Iron Ore (RTIO) has observed and safely managed fall of ground (FoG) events throughout the history of its open pit operations. These FoG events have been documented in a central database and recently visualised using ArcGIS. The entire dataset has been leveraged to compare the actual failed surface area to the surface area of the pits and design sectors they’re located in. This dataset has revealed the actual failure percentages fall well below industry norms, with actual failure percentages ranging between 0.0 and 3.5% for the majority of design sectors. This is somewhat expected for bulk mining operations with the requirement to meet such a high volume of production, with RTIO maintaining over 300 Mt annually. However, this dataset has become an invaluable tool to flag design sectors where there is an opportunity to challenge the original design assumptions and lead to a potential re-design and pit optimisation. The dataset also shows interesting relationships for actual failure rates by mechanism, scale and geological setting. By developing this database, RTIO has developed a powerful tool and methodology for design and risk management.

Keywords: slope stability, Probability of Failure, fall of ground, reporting, geotechnical data