复杂构造区煤层开采地下水数值模拟与应用

发布时间：2018-05-15 21:20

本文选题：数值模拟 + 构造控水　；参考：《华北理工大学》2017年硕士论文

【摘要】：煤矿开采对地下水的影响是一个动态且持续的过程,打破了地下水原有的补径排平衡状态,使地下水系统变得日益复杂。煤矿开采形成的采空区采掘深度不同、大小不同,其顶板的上覆岩层因失去支撑而依次出现冒落、塌陷和断裂裂隙,形成导水裂隙带,致使上覆含水层地下水向下部转移,导致矿井涌水,威胁矿井的安全生产。深入分析矿井水文地质条件,预测矿井涌水量对于防止矿井突水、淹井等矿山恶性事故、降低生产成本、保障矿山安全生产具有十分重要意义。以开滦东欢坨矿北二采区为研究区域,系统收集了矿井勘查与生产勘探获得的地质与水文地质资料,结合现场调查,全面分析了北二采区5煤层开采充水水文地质条件。通过对抽水试验数据、钻孔岩性与厚度、水位、涌水量、地质构造条件、采动破坏影响等综合研究,掌握了煤5顶板0~100m充水含水层的补给与边界条件、含水层非均匀分布储导水性、8煤层开采导水裂缝带含水层影响等规律。运用Visual Modflow数值模拟软件,建立了北二采区主要顶板充水含水层地下水数值模型,模拟了北二采区开采前地下水在长期的流动中形成的稳定流状态,获得东欢坨矿开懫前的初始水位与水流场。采用排水沟代替多个抽水井的方法实现了矿井采面排水,模拟了北二采区开采期间非稳定流地下水水位变化情况。依据煤5顶板长观孔东观27孔和东观39孔的观测数据对模型进行了拟合与检验,得出两个长观孔的历时拟合曲线和模拟区的渗透系数分区结果。利用经过识别验证的模型对5煤层开采工作面涌水量进行了模拟预测。结果表明:北二采区煤5以上0~100m强含水层为5、8煤层开采主要直接充水含水层,单位涌水量0.016~1.507L/s.m,渗透系数0.369~10.492m/d,裂隙非常发育,富水性强,且强烈不均。接受冲积层补给,水位、涌水量受构造影响。构造裂隙等导致含水层渗透系数非均匀性分布,形成六个分区。通过调整参数,东观27孔和东观39孔水位拟合较好,模拟结果显示5煤层开采预测最大涌水量5852.97m3/d,最小涌水量为1352.1 m3/d。
[Abstract]:The influence of coal mining on groundwater is a dynamic and continuous process, which breaks the original equilibrium state of recharge and discharge of groundwater, and makes the groundwater system become more and more complex. The mining depth of the goaf formed by coal mining is different and the magnitude is different. The overlying strata of the roof appear caving, collapsing and fracture fissures as a result of the loss of support, forming a water-conducting fissure zone, which causes the groundwater of the overlying aquifer to be transferred to the lower part of the overlying aquifer. Causes the mine to gush the water, threatens the mine safe production. Further analysis of mine hydrogeological conditions and prediction of mine water discharge are of great significance in preventing mine water inrush, flooding and other malignant accidents in mines, reducing production costs and ensuring safe production in mines. Taking Bei No. 2 mining area of Donghuantuo Coal Mine in Kailuan as the research area, the geological and hydrogeological data obtained from mine exploration and production exploration are collected systematically. Combined with field investigation, the hydrogeological conditions of water filling in coal seam No. 5 of Bei No. 2 Mining area are comprehensively analyzed. Based on the comprehensive study of pumping test data, borehole lithology and thickness, water level, water inflow, geological structural conditions and the influence of mining failure, the recharge and boundary conditions of 100 m water-filled aquifer with coal 5 roof are mastered. The influence of aquifer on water conductivity fracture zone in non-uniform distribution of aquifer is studied. By using Visual Modflow software, the groundwater numerical model of the main roof filling aquifer in Bei No.2 mining area is established, and the steady flow state of groundwater formed during the long term flow before exploitation in Bei er mining area is simulated. The initial water level and water flow field of Donghuantuo Mine before opening are obtained. The drainage of mining face is realized by using drainage ditch instead of several pumping wells, and the variation of groundwater level of unsteady flow during mining in Bei No.2 mining area is simulated. According to the observation data of 27 holes and 39 holes in the east of coal roof, the model was fitted and tested, and the diachronic fitting curves of the two holes and the partition results of permeability coefficient in the simulated area were obtained. The model verified by identification is used to simulate and predict the water inflow of 5 coal seam mining face. The results show that the strong water-filling aquifer of coal above 5 ~ 100 m in Bei No. 2 mining area is the main direct water-filled aquifer in coal seam No. 5. The unit water inflow is 0.016 ~ 1.507L / s 路m, the permeability coefficient is 0.369 ~ 10.492 m / d, the fissure is very developed, the water-rich is strong, and the water content is strong and unevenness. Accept alluvial bed recharge, water level, gushing water is affected by structure. Structural fissures lead to heterogeneous distribution of aquifer permeability coefficient, forming six subzones. By adjusting the parameters, the water level of Dongguan 27 well and Dongguan 39 hole is fitted well. The simulation results show that the predicted maximum water inflow of coal seam 5 is 5852.97 m3 / d, and the minimum water inflow is 1352.1 m3 / d.
【学位授予单位】：华北理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD745;P641

【参考文献】