Abstract： In order to liberate the coal resources under buildings and prolong the service life of the mine, an industrial test of layered mining of gangue in thick coal seam was carried out in No. 2 coal mine of Xingtai mine. The mass ratio of gangue to fly ash is determined to be 10:3 through laboratory experiments. The filling material enters the well bottom through the feeding hole and is transported to the working face by belt conveyor. In the process of use, the filling hydraulic support and waste scraper conveyor are improved to improve the filling efficiency and realize the parallel operation of mining and filling. Ground observation shows that the maximum surface subsidence is 85mm, and the damage level of buildings is within class I, which has achieved good control effect.
