Bellido, NG & Mendoza, PG 2024, 'Calibration of the PM4Silt model for polymetallic fine grained mine tailings based on laboratory testing results ', in AB Fourie & D Reid (eds), Paste 2024: Proceedings of the 26th International Conference on Paste, Thickened and Filtered Tailings, Australian Centre for Geomechanics, Perth, pp. 361-370, https://doi.org/10.36487/ACG_repo/2455_29
(https://papers.acg.uwa.edu.au/p/2455_29_Bellido/)
Abstract: The seismic response of the tailing dams is highly dependent on the seismic response of the mine tailings to be stored and given the recent failures of tailings storage facilities around the globe, it is essential to understand the mechanical behaviour of different mine tailings. This paper presents a geotechnical characterisation of thickened tailings from polymetallic deposits, composed mainly of lead, silver, zinc and gold. The laboratory tests have been performed on tailings samples obtained from the tailings storage. 
The geotechnical characterisation has been developed based on results from special laboratory tests, such as cyclic direct simple shear, static triaxial, resonant column, and torsional shear. Cyclic direct simple shear and static triaxial tests have shown that the contractive tailings are susceptible to liquefaction, and that their behaviour is similar to low plasticity silts and clays. The results from cyclic tests show flatter liquefaction resistance curves compared to sands, these observations seem consistent with what has been observed on natural silts and few previous studies on mine tailings. In order to model the behaviour of tailings in dynamic simulations, the PM4Silt constitutive model is calibrated based on the laboratory test presented here. 
The calibrated model can reproduce reasonably well the cyclic strength curves measured in the laboratory at different confining pressures. The results indicate that the PM4Silt model can be used to simulate the cyclic behaviour of thickened tailings.

Keywords: thickened tailings, polymetallic deposits, PM4Silt constitutive model, cyclic test