Mathematical and geomechanical model in physical and chemical processes of underground coal gasification

The formation of the stress-strain state of rocks in the several phase gasification processes was considered. Proceeding from the well-known principles of thermodynamics and phase formation of the multi-type rockmass under the influence of the temperature field, a geomechanical model of a two-layer artificially-formed shell formed during the gasification process by the method of variation feeding of the blowing mixture to the body of the gas generator was developed. The Neumann principle is used for the magnitude determination of the maximum stress vector, which involves the definition of the axial tensor of mechanical deformations through the anisotropy of the thermal expansion (the polar tensor of the second rank). This makes the possibility to create the base for a package of information programs creation. Such programs give the possibility to simplify the study of the rockmass deformation characteristics and to evaluate the stresses in a thermally changing environment. Researches are carried out by creating the final element system with the adaptation to the specific mining-geological conditions. These approaches are checked both for working out the coal reserves and for utilization of the mining waste products. Results of this investigation were included to the Roman Dychkovskyi thesis of the scientific degree of the Doctor of the Technique Sciences “Scientific Principles of Technologies Combination for Coal Mining in Weakly Metamorphoses Rockmass”. They contain the researches, which were conducted within the project GP – 489, financed by Ministry of Education and Science of Ukraine.