采煤工作面覆岩“两带”发育高度探测研究

Research on the Development Height Detection of the"Two Zones"of Overburden Rock in Coal Mining Faces

煤层开采后,覆岩发生变形、移动和破坏并形成“两带”(垮落带、导水裂缝带)。当“两带”沟通上部含水层时,将使沟通的含水层间发生密切的水力联系,对煤矿的开采造成较大影响。该文以宁夏银星一井111211工作面为研究对象,通过钻探取芯、钻孔冲洗液消耗量观测、钻孔彩色电视影像实测及采用现行规范公式计算验证等手段和方法,研究十二煤层采空条件下覆岩的变形及破坏规律,确定十二煤层“两带”发育高度。研究结果表明,十二煤层采空后的导水裂缝带高度为53.35 m,裂采比15.69∶1。垮落带高度为12.79 m,垮采比3.76∶1。探测研究成果,对采掘工作面充水水源的辨识、上覆含水层对工作面充水影响的评估、防隔水煤(岩)柱设计及采煤工作面顶板水患灾害防治提供依据和指导,实现水体下安全生产,提高煤矿生产能力和安全生产管理水平有着重要的意义。

After coal seam mining,overlying rock deforms,moves and destroys and forms"two zones"(caving zone and water-conducting fracture zone).When the"two zones"communicate with the upper aquifer,there will be a close hydraulic connection between the communicating aquifer,which will have a great impact on the mining of coal mine.Taking the 111211 working face of Yinxing No.1 well in Ningxia as the research object,this paper studies the deformation and failure law of overlying rock under the condition of mining of 12th coal seam and determines the development height of"two zones"of 12th coal seam by means of drilling coring,observation of the consumption of drilling washing liquid,drilling color TV image measurement,calculation and verification of the current standard formula.The research results show that the height of the water-conducting fracture zone after the 12th coal seam is 53.35 m,and the fissure ratio is 15.69:1.The caving zone is 12.79 m high and the caving ratio is 3.76:1.The research results provide the basis and guidance for the identification of water filling source of mining face,the assessment of the influence of overlying aquifer on water filling of mining face,the design of water-proof coal(rock)column and the prevention and control of water disaster of coal face roof.It is of great significance to realize the safety production under water body,improve the production capacity of coal mine and the level of safety production management.