A boundary model of terrain reconstruction in a coal-mining subsidence waterlogged area

Mining of coal resources in an area with a high groundwater level causes large-scale water accumulation on the surface, which brings great difficulties to land reclamation. To improve the reclamation efficiency, a boundary mathematical model of terrain reconstruction in the subsidence waterlogged area was established based on the Probability Integral Method (PIM) and the principle of equal amounts of digging and filling. The terrain reconstruction curve of deep-digging and shallow-filling was calculated through the linear combination of the surface’s predicted subsidence curve and the designed elevation line. The dividing boundary, inner boundary, and outer boundary of deep-digging and shallow-filling were defined. Finally, the whole subsidence area was divided into four different regions according to inflection points of the terrain reconstruction curve, and the ecological reconstruction schemes of agriculture, forestry, and fishery were put forward. The engineering practice of the 1013 panel in Wugou Coal Mine showed that 54.69%, 31.55%, and 13.76% of the subsided land were reclaimed for cultivated land, slope cultivated land, and aquaculture area, respectively, and all the subsided land was reasonably utilized. This method provides a new technology for eco-environment treatment in the subsidence area with a high groundwater level.