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, Australian Centre for Geomechanics, Perth, pp. 59-75, https://doi.org/10.36487/ACG_repo/708_2
Large scale, open pit copper mining in Chile involves the mobilization of large amounts of waste material
from the pit to areas specifically prepared to store this material. The challenge faced by some mines in the
Andean mountain range is the lack of available space for waste dumps given the steepness of the typical
mountainous topography. Because of this there is an ever more urgent need to design very high dumps that
are unprecedented in the world.
Usually verification of the stability of waste dumps does not pose a significant difficulty. However, in the
case of deposits that can be hundreds of metres high at the face, such as those planned by Codelco´s Andina
Division, it becomes necessary to have detailed knowledge of the geomechanical behaviour of the material.
In general, the studies in characterisation of coarse granular material have been done in relation to the
construction of rockfill dams. Waste dumps, as opposed to dams, are generally built simply by overturning
truckloads, which produce a low initial density. Additionally, the particles of material can reach sizes in the
order of metres, which is not common in dam construction.
The investigation and results of the characterization of the geomechanical properties of the waste material
from Codelco´s Andina Division is presented in this paper. In particular, characterisation of the particles
and large scale shear resistance tests were carried out in an attempt to simulate the field conditions in terms
of grain size distribution of the material and level of the expected loads.
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