条带残留煤柱膏体充填综采技术研究与应用

Research and application on the technology of paste backfilling fully mechanized in residual strip pillar

为了彻底解放建筑物下条带开采遗留煤柱资源,采用理论分析与现场实践结合的研究方法,对条带遗留煤柱膏体充填复采煤柱稳定性、覆岩结构变化特征和膏体充填技术参数进行了探讨,得出了合理膏体充填体强度、充填率、煤柱宽度等参数指标。研究表明:条带开采遗留煤柱膏体充填复采时合理的煤柱宽度为5.0 m;充填率不得低于70%;安全系数取k=1.5~2.0,当开采煤柱宽度小于50 m时,充填体28 d抗压强度不小于5.0 MPa;当开采煤柱宽度小于100 m,充填体28 d抗压强度不小于2.6 MPa。以济北矿区岱庄煤矿生产技术条件,提出了条带遗留煤柱膏体充填开采回收技术,并确定了合理的工艺参数。实测表明,膏体充填开采达到充分采动后,地表最大下沉值为220 mm,下沉系数为0.076,取得了良好的地表沉陷控制效果。

In order to fully exploit the resources of coal pillar after strip mining under buildings,the stability of coal pillar,the structure characteristics of overlying strata,and the technical parameters of paste filling on paste backfilling in coal pillar after strip mining were explored through theoretical analysis and field practice,and at such parameters as the proper strength of paste filling body,filling ratio,and the width of coal pillar were obtained.Research has shown that the proper width of coal pillar after strip mining is 5 m;the filling ratio shall not be less than 70%;when the safety factor is 1.5-2.0 and the width of coal pillar is less than 50 m,the strength of backfill material after 28 days is not less than 5 MPa;when the width of coal pillar is less than 100 m,the strength of backfill material after 28 days is not less than 2.6 MPa.According to the production technical conditions of Daizhuang Coal Mine in Jibei mining area,the study has suggested recovery technology of paste filling after strip mining,and the reasonable process parameters have been given.The measured results have shown that the maximum surface subsidence is 220 mm and subsidence coefficient is 0.076 after the full recovery of the paste filling mining,which achieved a good control effect of surface subsidence.