第三系砂砾含水层下工作面综放开采可行性研究

Research on feasibility of fully mechanized caving mining in working face under Tertiary gravel aquifer

为了提高多伦协鑫煤矿水体下综放开采的利用率,以1704-1工作面为例,运用地质勘探、实验室土工试验和理论分析等研究方法,分析获得第三系砂砾含水层性质和粘土层性质,从而确定了安全煤(岩)柱留设类型,进而确定安全煤(岩)柱合理留设尺寸和工作面安全开采厚度。结果表明1704-1工作面上方第三系砂砾岩含水层为弱富水性,安全煤(岩)柱可根据防砂安全煤(岩)柱留设;没有赋存砂砾岩含水层的"底粘区",粘土厚度大,流动性差,安全煤(岩)柱可根据防塌安全煤(岩)柱留设;1704-1工作面"底粘区"最小防塌安全煤(岩)柱留设为49.65 m,采用综放全厚开采;"底砾区"最小防砂安全煤(岩)柱留设为59.99 m,采用综放限制采厚7.78 m开采。

In order to improve the efficiency of full-mechanized caving mining under water body in Duolun Xiexin Mine,taking No.1704-1 working face as the example,the paper uses the geological exploration,laboratory geotechnical test and theoretical analysis methods to analyze the properties of Tertiary gravel aquifer and clay layer,based on which,it determines the type of safety coal （rock）pillar and reasonable size of safety coal （rock）pillar and safe mining thickness of the working face.The results show that the water-bearing property of Tertiary gravel aquifer above No.1704 -1 working face is weak,so the size of the safety coal （rock）pillar can be set refer-ring to the sand-proof pillar;in the clay area without the gravel aquifer,the clay is thick with poor mobility,so the size of the safety coal （rock）pillar can be set referring to the collapse-proof pillar;in the clay area of 1704 -1 working face,the minimum size of the collapse-proof pillar is 49.65 m,and the fully mechanized full-thickness caving mining is adopted;in gravel area,the minimum size of the sand-proof pillar is 59.99m,and the fully-mechanized caving mining with limit thickness of 7.78m is applied.