The Research Of Slope Protect Coal Pillar Reservation And Protection For Combining Open-pit With Underground Mining

Under the condition of combining open-pit mining with underground mining, two kinds of mining methods in mining influence domain are overlapping, showing a kind of mining effects affect another equilibrium system and make mutual induced or restrict each other between the two kinds of systems, therefore a complex dynamic system has been established.This paper has taken full advantage of the available geological data of PingZhuang west open-pit mine to establish a 3D geological model of coordinated exploitation, which realized mining industrial production data visualization. Based on this model and after a comprehensive analysis of domestic and foreign studies on combining open-pit mining with underground mining area features and mutual influences, the paper has used FLAC^3D to simulate the stress fields distribution in the area and the mutual influences between open-pit and underground mining. The paper has analyzed displacement law of the area near slope and slope surface under the condition of different breadth of slope protect coal pillar and has carried out the design to prevent the boundary coal steps of the open-pit mine from firing. The study of this paper has provided a guarantee for the coordinated exploitation of the open-pit and underground mining.