Keywords
open–underground mining
open-pit field
reserves beyond the open-pit contour
access schemes
shaft
side (pit wall) reserves
How to Cite
Abstract
The paper addresses the issues of improving the efficiency of ore deposit development in mountainous regions by substantiating options for accessing contour reserves under open–underground mining conditions. The relevance of the study is driven by the need to involve reserves located beyond the open-pit con-tour in mining under increasingly complex mining and geological as well as mining and technical conditions. Particular attention is paid to analyzing the feasibility of using the open-pit area as the main access element for the development of contour and off-contour reserves. It is shown that the use of the pit space for locating access workings and ore transportation makes it possible to reduce the volume of capital mine workings, shorten the time required to bring reserves into operation, and improve the economic efficiency of combined mining.
The study provides a comparative analysis of possible technological access schemes depending on the spatial position of reserves relative to pit elements, their depth of occurrence, and the adopted transportation system. Various options for accessing contour and off-contour reserves using shafts, inclined and horizontal workings, as well as the open-pit area, are developed and systematized. For each option, areas of rational application are identified with due regard to mining and geological conditions, pit parameters, and safety requirements. The obtained results can be applied in the design and optimization of access systems for ore deposits developed by open–underground mining methods in mountainous regions.
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Copyright (c) 2026 Misliboev, I.T., Mutavaliev, A.T., Tadjiyev, Sh.T. (Muallif)