The Study On Wide Strip Skip-mining And Its Ground Water Seepage Rule

Mining coal must destroy the intrinsic stress balance state of rock body, and wall rock begins to deform, move and destroy to obtain new stress balance, it not only brings about ruinous effect on buildings, but also easily change the supply and drainage condition of ground water, what's more it can increase penetrability and seduce ground water to inpour mine. Wide strip skip-mining is put forward for diminishing the destroy and effect on building and ground water, the two problems are researched and some elementary conclusions are obtained, the main content as follows: 1. It is analyzed that wide strip skip-mining, routine strip mining and full-pillar mining bring about dynamic and static deformation of ground surface, and their destroy and effect on buildings, the result of study shows that wide strip skip-mining is feasible. 2. Mining width and leaving width should be considered as a whole when the parameters of wide strip skip-mining are determined. The sinking curve and level distortion curve of the earth surface are analyzed by numerical calculation and graph on condition that mining width and leaving width are different size, and then more reasonable ratio of mining width and leaving width is presented. 3. The method for calculating equivalent permeability tensor is introduced , and the determinant criterions for the tensor validity are presented to assure the validity of fractured network equaling to equivalent continuum medium. 4. On the base of the two methods for obtaining permeability parameter of fractured rock, aiming at the limitation of corrected formula, corrected formula of integration permeability coefficient is put forward through numerical simulation of two-dimension packer permeability test. The corrected result shows the seepage characteristic of fractured rock anisotropy. 5. It is compared that the breakage degree of ground water move condition and the effect range of precipitation filler are brought about between wide strip skip-mining and full-pillar mining under two different conditions through numerical simulation, the range of precipitation filler is less in the course of wide strip skip-mining, it not only reduces the water quantity of influx mine, but also effectively protects ground water resource.