Extension of Water Flowing Fractured Zone during Coal Seams Mining in No.1 Mine of Tashendian Area

In coal seams mining in No. 1 mine of Tashendian area, three methods of theoretical analysis, UDEC numerical simulation, and physical simulation test were used in this research to analyze the extension height of water flowing fractured zone and the height of waterproof coal (rock) pillar.By calculation, it was obtained that, after each coal seam mined out, the height of water flowing fractured zone is about 33.7 m above 8-1 # coal seam, and the size of waterproof coal (rock) pillar greater than 44.06 m was reasonable; after upper and lower groups coal seam mined out, the height of water flowing fractured zone is about 81 m above 8-1# coal seam, and the size of waterproof coal (rock) pillar greater than 91.36 m was reasonable; after all coal seams mined out simultaneously, the height of water flowing fractured zone is about 95.1 m above 8-1 # coal seam, and the size of waterproof coal (rock) pillar greater than 105.46 m was reasonable.By numerical simulation, it was obtained that, after upper and lower groups coal seam mined out, the height of water flowing fractured zone is about 46.0 m above 8-1 # coal seam, and the size of waterproof coal (rock) pillar greater than 56.36 m was reasonable; after all coal seams mined out simultaneously, the height of water flowing fractured zone is about 76.0 m above 8-1# coal seam, and the size of waterproof coal (rock) pillar greater than 86.36 m was reasonable; By physical simulation, it was obtained that, after upper and lower groups coal seam mined out, the height of water flowing fractured zone is about 40.0 m above 8-1 # coal seam.And the waterproof coal (rock) pillar was about 70.0 m between and the aquifer.In situ production, each coal seam was mined out orderly.