The Key Technology Research And Application On Top Coal Caving Of Large Inclined Angle In Trend And Tendency In Xue Cun Mine

With the development of the coal industry, part of the old mine easy mining coalseam resources gradually dried up, had to mining some difficult mining coal seam,such as the deeply inclined coal seams，in the well area. In china the deeply inclinedcoal seams mining after decades of development, a variety of related theory andtechnology have made great progress, but generally the deeply inclined coal seams isonly a large inclination in the trend or tendency, for the theory and technology inbidirectional deeply inclined coal seams study also relatively less.In this paper, Taking XueCun Mine92714Face bidirectional deeply inclinedcoal seams as the research object, using numerical simulations, theoretical analysisand field practice integrated research methods to research the overburden structure，mine strata pressure behavior law，Top Coal Movement regularity and face equipmentantiskid.the results are shown as fllow：(1)By92714Overburden structure simulation analysis, the main roof of theseams are easily broken when level of forward propulsion and topple mining,bidirectional deeply inclined coal seams, due to a greater inclination, overburden afterfracture, under the action of its own weight, it will extrusion along the tendency，thereby increasing the stability of the structure of the main roof. For the same reason，the top coal caving is harder than forward propulsion and topple mining.(2)By analysis the data of pressure found in92714face that the working facepressure have a certain sequenc along the tendency，the pressure first in the workingsurface and then middle and lower face, which reflects the overburden fracture havea sequence.(3)By analysis92714Face principal stress field found that face overburdenstress changes in the entire mining process is relatively small, the stress concentrationis low, the maximum principal stress is about15~20Mpa; stress concentration areasare mainly in the larger inclined angle area of floor and coal pillar, therefore facelower roadway floor heave prevention and roadway support in the normal productionprocess should focus on strengthening.(4) Because coal seams have a greater inclination in tendency， top coalcaving will occur the horizontal and vertical displacement of the composite motion,the vertical displacement across the face did not change significantly, but the horizontal displacement presents the work surface portion than face bottomcharacteristics, therefore, should focus on the coal drawing in the lower part of theface.Through on-site industrial tests to determine the face caving method is a singleround and drawing interval is one cut one falling.(5)In the face bracket skid, the creative use of bracket in ZT12000/16/24typeends skid in the92714face ends, stand along the face towards layout, use the bracketto withstand the nose tip bracket to prevent face bracket down along the face. In thefield test process, end bracket made good support and non-slip effect.