Numerical modelling of fragmentation by blasting and gravity flow in sublevel caving mines

Authors: Yi, C; Johansson, D; Wimmer, M; Nordqvist, A; San Miguel, CR

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DOI https://doi.org/10.36487/ACG_repo/2205_66

Cite As:
Yi, C, Johansson, D, Wimmer, M, Nordqvist, A & San Miguel, CR 2022, 'Numerical modelling of fragmentation by blasting and gravity flow in sublevel caving mines', in Y Potvin (ed.), Caving 2022: Proceedings of the Fifth International Conference on Block and Sublevel Caving, Australian Centre for Geomechanics, Perth, pp. 963-974, https://doi.org/10.36487/ACG_repo/2205_66

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Abstract:
The sublevel caving (SLC) mining method is based on the utilisation of gravity flow of blasted ore and caved waste rock. Blasting is the initial and the major impact upon primary fragmentation and later material flow characteristics. A coupled numerical model was employed to investigate the fragmentation due to blasting and the gravity flow using the LS-DYNA code. In the coupled model, a loose discrete element model (DEM) was used to represent caved waste rock and a bonded DEM model was used to represent the orebody to be blasted, a particle blast method (PBM) was used to describe the detonation of explosive and a finite element model (FEM) was used to model the remaining orebody. The cumulative dilution of the ore by waste during extraction was evaluated. The results showed that the fragments at the upper part of the ring are coarse while the fragments at the lower part of the ring are fine. The change of the cumulative dilution along with the extraction is reasonable.

Keywords: sublevel caving, fragmentation by blasting, gravity flow, numerical modelling

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