Regularities of rocks zonal disintegration and methane emissions periodicity in mine roadways

Abstract

Abstract The article presents the results of studies on the establishment of stable relationships between methane emissions into degassing wells and their spatial location, stress-strain state of rock massif and mining operations process. Vibroacoustic and electrometric of mine control methods have been used to establish zoning and alternation of fractured zones in the rock massif during mining operations. Using the finite element method, zones of different permeability in the roof above the longwall face were determined, and a qualitative transition from compressive deformations to tensile deformations was revealed. Based on data from mine experiments at 157 degassing wells, patterns of repeatability of rocks zonal disintegration and periodicity of gas emissions into mine roadways depending on the distance to the moving longwall face have been determined for the first time. It has been established that the concentration of methane gas in a wells with distance from the longwall face changes according to a damped quasi-periodic dependence with recombinant changes in stress-strain states. For wells aimed at the goafs, the period of the quasi-periodic function increases by 40%, the amplitude decreases to 30%. The obtained dependencies make it possible to increase the efficiency of degassing.