The Ytc Pine Mine Remnant Ore Stoping Pressure Control Studies

Numerous mines are at telophase of mining and resources exhaust while there is a lot of residual ore in the goaf. In order to help relieve the resource crisis,the residual ore has to be drawn. But the technical conditions of residual ore are complicated, the goaf is open or the roof has fell. So the most difficult technical problem is to control ground pressure when the residual ore is drawn.Thesis chose residual ore recovery of room-and-pillar mining in Songshujiao Mine as subject investigated, built model of room-and-pillar mining with FLAC3D software. Then first mining was calculated while considering three different lateral-compression coeffecients.The result has been analyzed with rock mechanics,rock mass mechanics and compound rock mechanics so as to judge stability of pillars and wallrock, to get the regularity of workings ground pressure of three different lateral-compression coeffecients, to analyze the effect of panel pressure arch and to delineate the boundary of the panel pressure arch. Structure and parameter of room-and-pillar mining are reasonable through annlysis. Different sequence of mining brings different ground pressure to stand-by nugget and reasonable sequence plays an important role to control the ground pressure of workings. Thesis calculated three different sequence mining of deadweight stress pattern and found the regularity of workings ground pressure of three different sequence is similar.Some pillars could be drawn after first mining.But the workings ground pressure should be controled when the pillar is restored. Thesis analyzes stability of pillars and wallrock and regularity of workings ground pressure while drawing pillars at different position. Based on ground pressure control,the pillars next to panel barrier can be drawn.The roof may fall when drawing stress of the middle is large enough or the compressive stress of corner is beyond peak strength. Then the probable mode of roof caving of Songshujiao Mine is the corner break because of compressive stress beyond peak strength through analysis.