Study on reasonable width of coal pillar near the edge of panel based on prevention and control of rock burst

Abstract

The reservation of the coal pillar with reasonable width is the key to ensuring safe recovery of mining areas and working faces along the goaf. This paper studies the reasonable width of the coal pillar in the south wing of the 302 and the 301 panels by taking a mine in the Mengshan Base as an example, using theoretical research, numerical simulation and on-site measurement analysis. The three-zone theory is adopted to estimate the lateral bearing pressure of the goaf, showing that the width of the low stress zone is not less than 83 meters. The results of numerical simulation analysis show that the 20-meter coal pillar between the 1# and 2# ventilation roadways of the 201 working face has a high stress concentration, thus unable to meet the requirements for arranging small coal pillars. The high stress zone is concentrated within the lateral range of 90 meters. The micro-seismic data analysis shows that the micro-seismic accidents during the recovery of 202 working face are concentrated within the lateral direction of 80 meters. With the resource recovery and the impact of rock burst disaster prevention and control taken into consideration, this paper sets the reasonable width of the boundary coal pillar of the 302 panel to be no less than 85 meters.