煤炭开采条件下岩溶地下水疏排特征研究

发布时间：2018-08-14 17:24

【摘要】：煤炭开采对地下水的影响是一个持续且动态的过程。煤炭开采破坏了原有地层中的含(隔)水层,改变了天然地下水的补径排平衡状态,导致其影响区内地下水位下降、含水层疏干,使本已脆弱的地下水系统变得日趋复杂。近年来,随着煤炭开采规模的扩大和开采深度的加深,煤层顶、底板灰岩含水层的突水事故频发。因此,研究煤层开采条件下岩溶地下水渗流场的变化规律,预测矿井涌水量,对于安全采煤具有重要的现实意义。本文在充分分析国内外矿井涌水量预测成果的基础上,以山西省某煤矿为研究对象,进行了矿井涌水量的数值模拟研究。借助以往的水文地质勘探、抽水试验、水化学特征等基础资料,综合分析了研究区地质和水文地质条件；结合矿井充水水源和充水通道的分析,将研究区概化为非均质各向异性的三维渗流系统,建立了以石炭系太原组灰岩和奥陶系峰峰组灰岩为含水介质的岩溶地下水水流数学模型。通过对模型空间与时间的离散、定解条件的确定、源汇项的处理和水文地质分区参数的初步确定,应用有限差分数值法,对模型参数进行了识别和验证,最终建立起可以用于预测研究区岩溶涌水量的数值模拟模型。采用突水系数法分别确定了2#煤层底板太原组灰岩及11#煤层底板峰峰组灰岩含水层的突水危险性分区,2#煤层底板太原组灰岩及11#煤层底板峰峰组灰岩突水危险性区面积分别占研究区总面积的3.74%和11.26%。为了安全生产,必须对岩溶含水层进行疏干降压。论文采用大井法和数值模拟模型预测了岩溶水位达到安全水头时所需要的时问及矿井涌水量。研究表明：开采2#煤层时,采用大井法估算的矿井涌水量为99.36m3/h,数值法计算的矿井涌水量为140.4m3/h,且太灰含水层水位在疏降70天时低于临界水位；开采11#煤层时,采用大井法估算的矿井涌水量为400.41m3/h,数值法计算的矿井涌水量为396m3/h,且奥灰含水层水位在疏降90天时已低于临界水位。预测结果可作为研究区制定有效的防治水措施和安全生产的依据。
[Abstract]:The influence of coal mining on groundwater is a continuous and dynamic process. Coal mining destroys the aquifer in the original stratum and changes the balance state of recharge and discharge of natural groundwater. As a result, the groundwater level in the affected area decreases and the aquifer drains, the already fragile groundwater system becomes more and more complex. With the enlargement of coal mining scale and the deepening of coal mining depth, water inrush accidents occur frequently in the limestone aquifer of coal seam roof and floor. Therefore, it is of great practical significance to study the variation law of karst groundwater seepage field under the condition of coal seam mining and predict mine water inrush for safe coal mining. Based on the results, a numerical simulation study of mine water inflow is carried out in a coal mine in Shanxi province.
The geological and hydrogeological conditions in the study area are comprehensively analyzed with the aid of the basic data of hydrogeological exploration, pumping test and hydrochemical characteristics, and the three-dimensional seepage system with heterogeneous anisotropy is generalized by combining the analysis of mine water-filling source and water-filling channel, and the limestone of Carboniferous Taiyuan Formation and the peak of Ordovician Formation are established. The mathematical model of groundwater flow in karst area with limestone as aquifer is established. The parameters of the model are identified and validated by finite difference numerical method through the discretization of space and time, the determination of solution conditions, the treatment of source and sink terms and the preliminary determination of hydrogeological zoning parameters. Numerical simulation model of water inflow volume.
The dangerous zoning of water inrush of Taiyuan Formation limestone and 11# Fengfeng Formation limestone aquifer on the floor of 2# coal seam is determined by the method of water inrush coefficient. The dangerous zones of water inrush of Taiyuan Formation limestone on the floor of 2# coal seam and 11# coal seam in Fengfeng Formation limestone on the floor of 11# coal seam account for 3.74% and 11.26% of the total area of the study area respectively. The paper predicts the time needed when the karst water level reaches the safe water head and the mine water inflow. The research shows that the mine water inflow estimated by the large well method is 99.36 m3/h, the mine water inflow calculated by the numerical method is 140.4 m3/h, and the Taihuai aquifer is too lime. The water level is lower than the critical water level at 70 days of dredging, the mine water inflow estimated by large well method is 400.41m3/h, the mine water inflow calculated by numerical method is 396m3/h, and the water level of Ordovician limestone aquifer is lower than the critical water level at 90 days of dredging. The basis for it.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TD742

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