Conceptual tendencies to analyze coal-gas system state under the hydroimpulsive effect

¹ Institute of Geotechnical Mechanics named after M.S. Polyakov of the National Academy of Sciences of Ukraine, 2a Simferopolska St., 49005 Dnipro, Ukraine
² Dnipro University of Technology, Department of Underground Mining, 19 Yavornytskoho Ave., 49005 Dnipro, Ukraine

^* Corresponding author: avalansh@ua.fm

Abstract

The paper considers conceptual tendencies concerning the analysis of coal-gas system state within rock mass in front of a mine working stope in the context of hydroimpulsive effect on an outburst-prone coal seam. It has been shown that mining intensification is impossible without the improved efficiency of means indented to avoid gasdynamic phenomena taking into consideration the effect of technogenic factors on operation schedules. It has been determined that since grades of outburst-prone coal are of globular structure, its breakage may involve changes in molecular weight of coal substance and generation of methane and water molecules. In the context of a shear model of undermined rock mass, method of graphical analysis has been applied to determine areas of changes in border angles of demonstration of the initial and maximum deformation under the effect of rock bearing pressure. The determined dependences are described rather reliably by means of similar logarithmic curves which characterizes identity of their nature. Changes in filtration coal characteristics in the context of shear deformations have been considered. It has been proved experimentally that if injection pressure varies, periodically discontinuous fluid flow has initial, stable, and decaying stages being implemented in the forms of cavitation phenomena and high-frequency hydroimpulsive vibration. Sequence of methods to study parameters of hydroimpulsive action, evaluation of its efficiency, and control over a change in coal-gas system state of outburst-prone coal seams have been considered.