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According to the actual situation of repeat mining influence below upside coal seam, after studying fully ascending mining mechanism, spatial structure of the cover rock movement rules, relationship of asceding mining between time and space and its influencing factors, summarying the feasibility judging method of ascending mining of upper coal seam judged by adopting the "three zones", ratio criterion judging method. surrounding rock balance method, And analyzing from the face clean degree and the time interval of lower the mining coal seam mining, and fracture zones advancing height and concentrated stress distribution of the lower coal mining was simulated, In order to test fracture zones of growth altitude after the lower seven and eight coal seam mining, using drilling method, fracture zones growth altitude judged through three methods of borehole core broken degree, drilling slack circumstance and borehole television coal seam mining. Comprehensive three judgment method, upside coal seam mining locates above fracture zones of the lower coal seams, namely in bending sinking belt.In order to further understanding influence condition after the lower coal seam exploitation, and again made exploration at panel, explore the deformation and failure of the roof and floor of the upside coal seam. Detection results show that the roof and floor of upside coal seam downs slightly, coal and strata integrity, abutment pressure distribution etc, no exceptional, safely mining upside coal seam is feasible.According to the geological and the production technical conditions of mining face, and work face mining process is optimized, through mine pressure and rock mechanics control strata scope of working face and the direct roof collapsed for the first falling and the beginning and periodic pressure distance of the old roof are calculated and analyzed, and the mining reasonable supporting density was calculated.Researching on the thin seam upward mining key technology of close repeat disequilibrium mining influence is helpful for mine production increasing, prolonging service life, having the remarkable social and economic benefits. Attempting of 5 coal ascending mining, can not only enrich the ascending mining theory, and improve coal recovery rate, own important theoretic value and practical significance.
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