A parametric study on cave footprint capacity in discontinuous rock masses

Authors: Dehkhoda, S; Reusch, F Download Paper

Cite As:
Dehkhoda, S & Reusch, F 2024, 'A parametric study on cave footprint capacity in discontinuous rock masses', in Daniel Johansson & Håkan Schunnesson (eds), MassMin 2024: Proceedings of the International Conference & Exhibition on Mass Mining, Luleå University of Technology, Luleå, pp. 1322-1334.



Abstract:
Maintaining cave footprint stability during production necessitates a deep understanding of geological, geomechanical, and mining engineering factors that control cave initiation and establishment. This involves careful planning, ongoing monitoring, and flexibility to ensure the mining operation remains safe, economically viable, and socially and environmentally responsible. This study assesses the impact of fracture intensity, rock strength, and cave load on extraction level deformation and overall footprint capacity through a series of numerical scenario analyses. The analysis involves a submodeling approach with the discontinuum finite element numerical modelling method using a global mine scale model conducted in earlier studies. The boundary conditions for the submodels are derived from the global model to maintain the high similitude with displacements and the distribution of damage around excavations with resolution to a sub-bolt length scale. The paper will detail the model construction process and formulation of the constitutive model for the rock mass, defects, and ground support. The study's outcome is an overview of the upper- and lower-bound performance levels, representing the most and least favourable conditions for the tested scenarios.