Purpose. To substantiate the parameters of computer modeling of the mining area with a step-by-step movement of the working face, as well as taking into account the changing presence of sandstones that lie in the top of the reservoir, to predict the effect of sandstones on the nature of the distribution of convergence in the longwall and the technology of working excavation in the conditions of the mines of Western Donbass. Methods. The work uses a statistical analysis of the geological and technological conditions that are inherent in the coal mining enterprises of the Western Donbass. Also, a comparison was made of the parameters of the experiment of computer modeling of past studies, on the basis of which, a combination of new features was introduced and changed, which is aimed at choosing the optimal modeling parameters. Results. The substantiation of the parameters of the modeling experiment is presented, such as: the choice of the length of the working face, the depth of development of coal seams, the distance of the working face withdrawal from the assembly chamber, the values of the thickness of sandstones that lie in the roof of the coal seams, the choice of values of the distance of occurrence of sandstones above the roof of the coal seam, as well as geometric parameters of the computer model. Based on the justification of the parameters, a plan for conducting experiments was drawn up, the number of which was 225 units. Scientific novelty. As a result of the substantiation of the parameters, an additional combination of new features in existing studies was proposed for the first time, namely, to include in the experiment the presence of coal seams in the top – sandstones with variable thickness, the distance of occurrence above the seam, several standard sizes of the length of the working face were also included, the value of the development depth, the distance of the exit of the working face from the assembly chamber. Changing the above parameters will make it possible to compare the difference in the effect of the results of each experiment separately, depending on the change in each of the parameters, as well as to understand and generalize the idea of ​​the nature and causes of emergency longwall stops associated with the landing of powered support sections “on a hard base”. Practical significance. Substantiated modeling parameters make it possible to most adequately reflect the processes occurring in the rock mass, as well as to clarify the parameters of the reference rock pressure zones, unloading zones, as well as the nature of the change in the distribution of convergence in the longwall. The data obtained as a result of modeling can be used to select and substantiate an effective method for managing the state of the rock mass around the working excavation, which will eliminate the planting of powered support sections “on a hard base”, thereby increasing the efficiency of coal mining in the Western Donbass.

Purpose. The purpose of the research is to optimize the parameters of calculations in the spatial modelling of geomechanical processes during the advancement of the face. Method. The statistical method of research of mining and technical and geological data is used in the work, which is aimed at collecting primary statistical material, processing, systematization and grouping by common features, from characteristics of individual elements to generalizing indicators in the form of absolute, relative or average values of ordering, data processing and interpretation. Results. The cluster analysis of conditions on mine fields is presented. Of the fifteen mining and geological parameters that affect the step of planting the main roof, two homogeneous groups of minefields were identified to simplify the calculations, and further, to find objective patterns. A dendrogram of minefield typification is constructed. Scientific novelty. On the basis of the collected materials of the technical documentation on the coal mining enterprises of DTEK Pavlogradugol, by applying cluster analysis, for the first time the minefields were typified with the help of mining and geological conditions affecting the efficiency of coal mining models. Practical significance. Cluster analysis will significantly reduce the amount of calculations in the modelling of geomechanical processes. To increase the reliability of calculations by probabilistic and statistical representations of the nature and mechanism of planting the main roof. The typification of conditions, in the future, will allow modelling of stepwise movement of the face in the spatial geomechanical model of the excavation site, to predict the impact of mining and geological conditions on the technology of treatment, which will increase the efficiency of coal mining in Western Donbas.

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Purpose. Determination of a rational option for using a type of mechanized fastening in the conditions of simultaneous flooding of mines and mining operations, taking into account the manifestations of hydrostatic pressure formed in the main roof of the coal seam. Method. The research used the method of numerical modelling and analysis of the displacement of the sole and roof of the coal seam and the prediction of the step-by-step progress of the cleaning pit in the layered transversely isotropic massif of rocks using the Solid Works 2019 software package. Results. Obtained statistical parameters of the use of mechanized fastening in the hydrogeotechnical conditions of the mines of Western Donbas based on the collected actual data of the mining enterprises of PJSC «DTEK Pavlogradvugillia». The reasonable feasibility of using a supporting and fencing four-pillar, two-row mechanized fastening of the KD-80 type by comparing the results of modelling its operation with a two-pillar single-row fastening of the Ostroj-70/125 type in conditions of a layered massif with manifestations of hydrostatic pressure. Scientific novelty. For the first time, a geotechnical forecast was performed on the basis of numerical comparative modelling of the operation of single- and double-row mechanized fasteners in the conditions of simultaneous flooding of the mine and mining operations, taking into account the manifestations of hydrostatic pressure, which is formed in the main roof of the coal seams of the mines of Western Donbas. When using two-pillar single-row fastening, the value of convergence can increase by more than 33%, in comparison with four-pillar two-row mechanized fastening of the support-fencing type. Practical significance. The research results make it possible to determine a rational option for using the type of mechanized fastenings for the complicated hydrotechnical conditions of coal mining from ultra-thin coal seams of the mines of Western Donbas, as well as to develop recommendations for technological improvement of mining operations, to minimize accidents associated with the subsidence of sections of mechanized fastening «on hard base», which significantly increases the efficiency of coal mining.