Study on Impact Mechanism of Double Withdrawal Channels in Fully Mechanized Mining Face Based on Overburden Theory

Based on the theory of overlying rock, the impact mechanism of the double-retracement passage of the fully-mechanized mining face is studied based on the method of field measurement, numerical simulation and theoretical analysis based on the background of the terminal section of a fully-mechanized mining face in Ordos. The main conclusions obtained are: the results of field measurement and numerical simulation show that the coal pillars between the main withdrawal lane and the working face in the final mining stage of the fully mechanized face adopting the double-lane withdrawal scheme will bear higher concentrated stress. When the capacity reaches the limit, the risk of coal pillar impact is the highest; according to the theoretical analysis results, the impact mechanism of the double retreat channel in fully mechanized coal mining face is “DLZ” and the high-level rock layers within the range of “SLZ” that it bears will transmit higher static abutment pressure. The stress conditions for the danger of impact on the coal pillars of the retracement road are reached. Theoretical analysis, simulation, and on-site research results are in good agreement; the control mechanism of rockburst with double withdrawal channels in fully mechanized mining face is: determine reasonable pressure relief parameters, release coal accumulated energy through the construction of large-diameter boreholes, and strengthen the bolt support Density is used to reduce the degree of damage to the surrounding rock structure, and at the same time strengthen the monitoring and early warning of dangerous areas to ensure that the surrounding rock of the roadway is in a state of “low stress and strong support”.