Study on the Law of Overlying Rock and Slope Instability in Open-pit to Underground Room-pillar Mining Based on MatDEM
As open-pit mines turn into underground mining,it is particularly important to study the stability of overlying rock and slope system after secondary disturbance.Taking a large open-pit to underground room-pillar mining mine in Jiangxi Province as the research background,a numerical simulation model was established using MatDEM discrete element software to calculate and analyze the displacement,stress and kinetic energy of overlying rock and open-pit slope under the disturbance of room-pillar mining.The results show that with the formation of the mined-out area,the overlying rock of the stope form an ellip-tical stress reduction zone centered on the mining area.The rock strata in this area have been significantly damaged and moved along the mining direction.The stress change of the stope roof shows four stages of stress concentration-stress increase-stress re-construction-stress balance with the mining process.The underground mining makes the overlying rock and the open-pit slope of the stope have a large displacement.The rock movement area and rock movement energy of the overlying rock are larger than those of the slope,and the change of the overlying rock shows more sensitive characteristics.The research results can provide reference for the mining design of similar mines.
secondary disturbanceopen-pit to underground miningoverlying rockslopeMatDEM