Geogenetic and geomechanical typification of the weakening surface in the layered rock massif of the Western Donbass

Purpose is to generalize typical geogenetic and geomechanical characteristics of the surfaces of loosening within the layered coal-bearing formation of the Western Donbas rocks as the potential criteria of both course and assessment of geomenchanical processes impacting the longwall-gate road system interaction, and identifying geotechnical terms to drive and use the gate roads. Methods. The problem to define surfaces of loosening as one of predictive factors of rock breakage in longwalls as well as its impact on interconnection with gate roads is solved based upon the data of geological and operational explorations of a mine field. Characteristic of geological material forming surfaces of interlayer loosening in terms of vertical and horizontal rock tensile strength being the determinant of geomechanical anisotropy of the layered rock mass is taken as a basis. Findings. Geogeneticandgeomechanical typing of the surfaces of loosening within the layered Western Donbas rock mass has been substantiated. It is based upon separation of five types of surfaces of loosening beyond tensile strength and decrease in textural anisotropy factor. Its limit minimum values correspond to the rock moisture being more than 5 %. Originality. Relying uponthedataof the laboratory-based tensile tests of core and mine samples as well as following petrographic analysis of interlayer rock material identifying lithological and succeedent geomechanical stratification of carbonaceous formation, five types of the surfaces of loosening have been identified towards an increase in their strength and decrease in textural anisotropy factor on the edge of rock moisture being up to 5 %. Practical implications. Typingof thestratifiedsurfaces ofloosening has been used to assess potential stability of roof rocks of coal seams while drafting calendar plans as well as geotechnical regulations for coal extraction in projects of such Western Donbas mines as Pavlohradska, Stepova, andYuvileina.