Deterministic factors of safety for the evaluation of the stability of tailing dams: a reflection
DOI:
https://doi.org/10.24849/j.geot.2021.151.04Keywords:
Tailing Dams, Deterministic factors of safety and risk, Flow LiquefactionAbstract
The stability assessment of mining tailings dams has undergone an evolution in recent years, supported by the information reported by expert panels, following the numerous cases of ruptures. The management of the security levels to be adopted has been increasingly associated to the need of introducing conditioning factors for risk analysis that take into account the variabilities and uncertainties, taking into account the probabilities of the factors of stability of the dam and the implications on loss of lives and environmental impact after rupture. These characteristics of the geotechnical materials should be integrated into the distinct conditions of permanent state and the frequent and rare actions, etc. While these new methodologies are not implemented in existing structures, periodic technical safety audits are still based on deterministic Factors of Safety that seek to ensure stability of these assets. In this article, these safety factors will be discussed in the light of good international engineering practices and considerations will be made on how to ensure characteristic values of the parameters used in the stability assessment calculations and how it is considered that these analyses should be conducted under drained and undrained conditions and which equilibrium models should be used.
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