Abstract:
For preventing the support crushing and water inrush accidents during mining under unconsolidated confined aquifer in Qidong Coal Mine, failure characteristics of overburden strata during initial mining period of regulate inclination mining face were studied combining with the mining conditions of 8
222 working face. Results indicated that the suspended layer of the key strata is triangular in the case of regulate inclination mining during the initial mining period, and when the large size of the mining area exposing to a certain extent, first breaking of the roof occurs and causes the partial roof weighting of the working face. With the increase of the size of the face, the main roof breaks partially, which makes the local pressure behavior area gradually transfer to the middle and the tail of working face, thus avoiding the large area and fierce weighting or even the support crushing caused by the first breaking of the roof under high water pressure. Therefore, the oblique mining has a positive meaning in the prevention of support crushing.