Filling-reclaiming method for building land in coal mining subsidence areas

The invention provides a filling-reclaiming method for building land in coal mining subsidence areas, which belongs to the technical field of mining and is used to solve the problem of developing and utilizing coal gangue. The invention adopts a technical scheme that the method is implemented according to the following steps: a, draining accumulated water in reclamation areas and clearing silt; b, striping and stockpiling surface soil; c, determining the thickness and density of coal gangue for hierarchical backfilling through a vibration pressure test; and d, performing hierarchical backfilling compaction on the coal gangue and soil. The method has the following main advantages that: 1, the ways of utilizing the coal gangue are expanded, and environmental pollution caused by stockpiling the coal gangue on ground is reduced; 2, the situation that building land is increasingly short is alleviated by reclaiming subsidence land to be the building land; and 3, the treatment for coal gangue for large-area hierarchical backfilling by a hierarchical vibration-compaction method is economical, reasonable and ideal in compaction effect, can improve the compactness and bearing capacity of coal gangue layers, and can prevent the spontaneous combustion or efflorescence of coal gangue foundations and the separation of harmful substances from polluting local environment because hierarchical compaction greatly reduces porosity and isolates air.