Title: Influence of large-scale structures on the stability of the hangingwall in a caving mine: a modelling study
Authors: Sraj Banda Umar; Catrin Edelbro
Addresses: Division of Mining and Geotechnical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, SE-97187, Sweden ' Division of Mining and Geotechnical Engineering, Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, Luleå, SE-97187, Sweden
Abstract: The Printzsköld orebody in the Malmberget mine of Northern Sweden is currently under production and is centrally located in the mining area. The effects of the on-going sublevel cave-mining in this orebody are currently investigated with respect to cave development with an initial emphasis on the effects of stress redistribution and potential rock mass yielding. In this study, three-dimensional discontinuum modelling of the Printzsköld orebody is presented, in which the effect of three pre-existing large-scale geological structures have been studied. The results of the present study showed low stress build-ups in the crown pillar and cave bottom, due to shear slip developing along the structures. The presence of large-scale structures has no significant effects on the far-field stresses as shear slip along these structures is confined to cave boundaries. An analysis of the shear strength of the structures showed larger effects of slip on reducing friction angle than the reduction of cohesion.
Keywords: large-scale structures; shear slip; shear strength; friction angle; hanging wall stability; Printzsköld orebody; failure mechanism; numerical analysis; caving mines; discontinuum modelling; 3D modelling; Sweden; mining industry; stress redistribution; rock mass yielding.
International Journal of Mining and Mineral Engineering, 2016 Vol.7 No.4, pp.294 - 312
Received: 06 Oct 2015
Accepted: 08 Jun 2016
Published online: 21 Oct 2016 *