东荣一矿“天窗”下充填安全开采上限研究

Research on the Safe Upper Limit of Backfill Under the Skylight in Dongrong No.1 Coal Mine

针对双鸭山东荣一矿"天窗"下压煤,导致生产接续紧张的实际问题,采用粉煤灰基胶结充填法提高安全开采上限。通过等价采高模型分析得出9#煤层充填开采顶板最终下沉量为1.38×10-3 m,顶板保持完整,煤体上覆岩层稳定,抑制了导水裂隙带;当全部煤层充填开采时,安全开采上限可提高至保护层底界面标高-127 m处,增加可采储量15.3 Mt;生产实践和FLAC3D数值模拟验证结果表明:随采随充时顶板稳定不会产生塑性破坏,为类似条件矿井充填开采提供了借鉴范例。

Aimed at the sustainably tight production caused by the coal mining under skylight in Dongrong No. 1 coal mine of Shuangyashan, cemented backfill with fly ash was used to improve safe upper limit. Through the analysis of equivalent mining height, it obtained that at 9# coal seam, the total subsidence of roof was 1.38 ×10-3 m, the roof kept complete, and the overburden of coal was stable, so as to restrain the water flowing fractured zone during filling mining. When all coal seams used backfill, the safe upper limit can be improved to the protective layer of -- 127 m and the re- coverable reserves can be increased by 15.3 Mt. Production practice and the results of FLAC3D numerical simulation showed that plastic damage in roof would not occur during mining and filling, which provided reference for the backfill mining in similar mines.