The dissertation is devoted to solving the actual scientific and technical problem of establishing the patterns of changes in the stress-strain state of gas-saturated structurally-heterogeneous rocks under the influence of mining, the emission of methane gases and radon daughter decay products into mine workings, as well as substantiation of risks complex indicators of for the of geomechanical and gas-dynamic processes dangerous development scenarios in the rock massif, development of methods and software for geomechanical and radiometric control of the mines production environment safety parameters.
The mathematical model for assessing the destruction zones in gas-saturated and water-cut rocks has been further developed, it differs in the use of the joint consideration of natural structural defects, main cracks, rock layering, reservoir gas pressures, the presence of water in cracks and pores, as well as the determination of the main deformations components invariants, which characterize the changes in the shapes and volumes of the pore-fracture space, where areas of gas supply are formed in the process of mining. For the first time, regularities of changes in the pore and fracture area shape and volume at different stages of the adjacent longwall mining have been determined basing on parameters of fracture system orientation and spherical part of the strain tensor.
The relationships were formulated, which established interdependence between the parameters of geomechanical process and parameters of gas-dynamic process, which can be integrated into information systems for preventive control of the state of working environment in the mines. A decaying quasi-periodic dependence of methane emissions into wells has been established, which allows you to determine the layout of wells to improve the efficiency of degassing.
It is further for the first time a stable interdependency between dynamics of changes in methane concentration and reduced concentration of radon decay products when deviation of concentration change is within ± 20 % are disclosed. These interdependencies can be a basis for designing new methods for prediction manifestations of geomechanical and gas-dynamic processes. The method of controlling the safe state of rocks has been further developed; it differs in the use of the determined ratios between changes in fracture system parameters and changes in alpha-radiation activity of some radon isotopes, methane concentrations and their correlation.
The method for assessing of the mining operation safety levels was further developed, it differs in the use of the complex indicators that determine the rock massif preparedness for hazardous scenarios of the geomechanical and gas-dynamic processes. Indicators are determined by a statistically significant number of parameters of previous events or by trends and analytical forecasts of further events using fuzzy logic models and expert rules.
A number of techniques, recommendations, software and regulatory documents have been developed and implemented: on the methods of controlling the power characteristics of the "support-massif" system; of degassing technologies; forecasting dangerous manifestations of rock pressure using of the radiometric control method; software for modeling geomechanical and gas-dynamic processes, personnel management and remote safety control; Industry Standard of Ukraine "System for ensuring reliable and safe functioning of mining workings with anchorage. General technical requirements"; the final version of the Industry Standard of Ukraine "Production and labor safety management system in coal industry of Ukraine. Typical regulations", regulating the requirements for safe mining and risk management in accordance with international standards OHSAS 18001 and ISO 9001. Developments have social, environmental and economic effects. The economic effect from the implementation is 4.8 million UAH.
