Principles of mining-geological classification for maintaining mine workings in conditions of weakly metamorphosed rocks

Purpose. The purpose of this research is to group the mining-geological conditions of a stratified mass containing weak rocks in the Western Donbas (Ukraine) and to substantiate recommendations for rational supporting and protecting system parameters for reused mine workings. Methods. The research was conducted by combining analytical methods for studying the processes of rock mass deformation in the zone of stope operations with experimental measurements of rock pressure manifestations. As a connecting link, ideas about the development mechanism of the coal-overlaying formation shear process and its peculiarities for the mining-geological conditions of the Western Donbas were studied. The obtained patterns were taken into account in the calculation model as a component of load formation, as well as in supporting and protecting system for extraction drifts. A methodology for computer modeling was determined based on the condition of the maximum possible representation of the design peculiarities of frame and roof-bolting supports. The developed models were tested, which confirmed their adequacy to real objects. Findings. The complex of conducted studies made it possible to develop an array of calculated texture variants that reflect the probability of dividing lithotypes by their thickness in the rock layers of the immediate and main roof and bottom. Based on the results of a number of computational experiments to study the effectiveness of the recommended options for supporting and protecting systems, the distribution of the stress-strain state in the load-bearing elements of the system has been determined. Principles of grouping of mine working maintenance schemes have been created, which cover most of the mining-geological conditions of mines in Western Donbas. Originality. To achieve the reliability of the results, a complex of peculiarities and mutual influence of the geomechanical system elements has been studied. The patterns obtained as a result of multifactorial modeling have revealed the link between the strengthening of rock layers in the form of their discrete disturbance and the formation of a system of interacting plates, which intensifies the process of pressing-out a partially strengthened border mass. Practical implications. The novelty of the research is in generalized principles of grouping structural-technological schemes for maintaining extraction drifts. As a result, three groups of mining-geological conditions for the operation of extraction drifts planned for reuse have been identified. Three variants of schemes for maintaining extraction drifts for the conditions of mines in the Western Donbas have been proposed and studied.