ASSESSMENT OF THE PARAMETERS OF THE UNLOADING ZONE AND ITS USE FOR THE SAFE MINING OF OUTBURST-HAZARDOUS COAL SEAMS

Abstract

Meta. The purpose of the research is to substantiate the main characteristics of the unloading zone in the bottom-hole part of the seam and to clarify the parameters of its use for the safe mining of outburst-hazardous coal seams. Research methodology. The article analyzes the results of determining the size of the unloading zone by various methods of monitoring the effectiveness of the measures taken and the danger of coal mining in this zone. Results. The definition of the unloading zone as some degassed part of the mountain massif with destroyed or extracted coal is formulated, when discussing the obtained results. It has been established that in this zone there is a possibility of excavation coal to a given depth without anti-emission measures with the possibility of adjusting the amount of excavation by the depth of the unloading zone, taking into account non-reducing advance. The size of the unloading zone is determined by the time bottomhole sludge, taking into account: SSS (stress-strain state), PMP (physical and mechanical properties), geological factors and technology of destruction of the array. Scientific novelty. The size of the unloading zone may vary depending on the technological factor (excavation technology). For example, with a fast plow cut, the zone does not have time to form, i.e. when a plow (combine) either takes out a strip along the entire length of the lava or can be cut forward by 2-3 m. Practical significance. The performed studies established the fact of the formation of an unloaded zone in the bottom-hole part of the formation. The time interval for the formation of an unloading zone is from 1 to 3 hours for mechanized coal mining and up to 24 hours for explosive breaking of coal, which is practically used in regulating the duration of technological processes. The unloading zone on outburst-prone formations varies from the minimum dimensions close to zero to several meters.