Investigation into the Stability and Liquefaction Susceptibility of a Tailings Dam in Brazil during Excavation

September 26, 2024

Tailings dam failure can lead to catastrophic consequences including loss of human lives, and damage to existing infrastructure. Therefore, examining the stability of a tailings dam during construction and assessing the potential for triggering liquefaction in the tailings is important. This paper focuses on an assessment of the excavation process for an existing tailings dam in Brazil. The evaluation involves the implementation of a 3D deformation model using FLAC3D. The construction stages of the dam were simulated and the stress-state for each element in the models was compared with the instability locus and the critical state line by evaluating the ratio between the stress state and the slope of the critical state line. The removal of tailings during the excavation process results in progressive reduction of liquefaction susceptibility. However, there is a potential to trigger liquefaction close to the surface which needs to be managed during excavation.

Saaly, M., V. Nguyen, M. Vieira, H. Ninanya and C. de Andrad. 2024. “Investigation into the Stability and Liquefaction Susceptibility of a Tailings Dam in Brazil during Excavation.” in Proceedings of GeoMontreal 2024. Resilient Geosciences for Future Generations, 15-18 September 2024, Montreal, QC.