Методика цифрової обробки зображень для аналізу тріщинуватості та деформаційної поведінки шаруватого гірського масиву при фізичному моделюванні

Purpose. To develop a digital image processing methodology for the quantitative analysis of fracturing and deformation behavior of a layered rock mass under physical modeling of coal seam extraction, as well as to identify the characteristic stages of roof strata failure above the mined-out space. Method. The study was carried out using physical modeling with equivalent materials reproducing the layered structure of the rock mass. The development of the mined-out space was simulated step by step, with photographic recording of the model state at each stage. Image processing included preliminary preparation, conversion into a negative image, binarization of fracture structures, generation of fracture density maps, and maps of fracture density difference relative to the initial state. For the quantitative description of damage evolution, the average fracture density, its increment between stages, as well as the rate and acceleration of change in this parameter were used. Results. The proposed methodology made it possible to identify the spatial localization of fracture formation zones and to trace their evolution at different stages of modeling. It was established that fracture development is stage-dependent and includes an initial phase of local delamination, a phase of active formation of the failure zone, a stage of intensive development of the caving arch, and subsequent stabilization of the process. It was shown that the moment of primary roof caving is accompanied by a sharp increase in fracture density in the central part above the mined-out space and by an increase in the rate of its change. The fracture density difference maps relative to the initial state made it possible to identify newly formed zones of structural disturbance and to refine the boundaries of active failure. Scientific novelty. A methodology for digital image processing of physical models of a layered rock mass has been proposed which, unlike traditional visual analysis, provides a quantitative assessment of fracture development using maps of fracture density, its increment, the rate of change, and the acceleration of change. It was established that primary roof caving is preceded by a localized increase in fracture density and by accelerated accumulation of damage within the future failure zone. Practical significance. The developed methodology can be used to improve the objectivity of physical modeling results, identify critical stages of roof deformation and failure, compare models with different structures of the immediate roof, and assess the influence of mined-out space parameters on the character of caving. The obtained results can be applied to the interpretation of layered rock mass failure mechanisms and to the verification of numerical geomechanical models.