Geotechnical justification of primary cutting of the ore body of rich ore deposits of “Glubokaya” mine using methods of stepwise numerical simulation under gravitational-tectonic stress field conditions

Abstract

With regard to mining at depths the issues of ensuring the chambers stability, the choice of their orientation and the support selection still at the design stage are particularly relevant. At depths, near large tectonic disturbances, the factor of natural rock pressure starts to play a defining role in the underground structures stability, and the constant growth of requirements for improving safety of underground structures predetermines the need to incorporate modern approaches to identify the stressstrain state using numerical simulation. Making design decisions without simulation can lead to a decrease in economic performance and production safety, and sometimes entail the impossibility of full recovery of reserves. The finite element simulation used in this work as one of the main methods for determining the optimal option for primary cutting of the ore body and mining a rich ore body located in close proximity to large-scale tectonic disturbance that provokes a complex stress state of the ore body itself. On a practical level, the finite element method can be discredited, and therefore a description of the sequence of techniques for constructing and calibrating finite element models of primary cutting of the ore body (mining options) is required for correct identification of the most suitable mining option, that is done in this work. The integrated approach includes: formation of complex spatial geometric model of ore bodies, taking into account the morphology of bedding; separation of the model into stages of development and forming different variants of development; determination of borderline conditions for Cauchy tensor correct task; determination of deformation model and assignment of physical and mechanical parameters; carrying out verification calculations; calculation of all model variants, their analysis and selection of the most optimal ore deposit mining technique; interpolation of data into geomechanical block model for the possibility of selecting and substantiating the supports parameters and calculating the stability of chambers using analytical tools.