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Mechanism and feasibility of partial back-filling technique for water protection mining

Apertures in overlying strata are often as channels for groundwater penetrating. Especially for shallow-buried coal seam, that may be inducing damage to ecological environment by ground water table decline and disasters such as inrush of water and sand to coalface. Therefore the distribution characteristics and development of water apertures are very useful to design environmental and safety mining methods. Based on the analysis on distribution characters and development of water aperture, the mechanism and feasibility of partial back-filling method were studied by numerical simulation software 3DEC. The results show if the regions, such as places of first weighting and periodic weighting happened, were filled that most groundwater neither leak to workface to arising disaster, nor induce damage to ecological environment.