Substantiating the optimization solutions for the mine working fastening system interaction with the enclosing rock mass

Purpose. Determination of the rational interaction modes between the fastening system and the extraction working enclosing mass in the zone of stope operations influence.Methods. An algorithm for searching for optimal solutions for the interaction modes between the fastening system and the coal-bearing mass has been substantiated. The deformation-strength characteristics of the fastening system elements have been agreed. The design parameters of the support elements have been optimized according to the criterion of their equal strength. According to the optimal parameters, a methodology for calculating the function that describes the rational deformation-strength characteristic of the fastening system, depending on the mining-geological conditions, has been developed and substantiated.Findings. Computational experiments have been conducted to determine the rock mass deformation-strength characteristic. Based on the normative documents, the sizes of the natural equilibrium arch have been calculated. The adequacy of methodical principles for minimizing the load on the fastening system has been proved. The patterns for the influence of geomechanical factors on the choice of optimal parameters of the fastening system deformation-strength characteristics have been determined. A methodology for calculating the rational parameters of the fastening system and its constituent elements has been obtained.Originality. Combined studies of minimizing the load on the fastening system have been conducted. The patterns for the influence of geomechanical factors on the choice of load-bearing capacity and the yielding property value of the fastening system have been determined. Regression equations have been obtained for calculating the fastening system optimal parameters with a geomechanical index of working conditions. This enables implementation of a unified strategy for resource-saving improvement in fastening systems.Practical implications. A methodology has been developed for obtaining the weakening mass deformation-strength characteristic, depending on the depth of mine working location, the texture of the rocks in the coal-overlaying formation and its strength properties. The applicability of the methodology for the implementation of a unified strategy of resource-saving improvement of the mine working fastening systems for the Western Donbas mines has been proved.