METHOD FOR DESIGNING KEY PARAMETERS OF PROTECTIVE COAL SEAM BACKFILLING MINING

The present invention relates to a method for designing key parameters of protective coal seam backfilling mining, which is suitable for solving the problem of gas pressure relief of a close-range coal seam group, and comprises: step 1, according to the thickness, seam spacing and gas content of coal seams in the close-range coal seam group, preliminarily selecting the position of a protective coal seam and the position of a protected coal seam, the protective coal seam being an upper protective coal seam; step 2, on the basis of the actual geological conditions and coal petrologic parameters of the selected protective coal seam and the selected protected coal seam, obtaining the length x0 of a corresponding coal seam yield zone when the seam spacing is taken as the maximum plastic failure depth hmax of a floor rock mass, determining an equivalent mining thickness hd, calculating the final height hc of a backfilling body, and forming a protective coal seam backfilling mining key parameter calculation model; a