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1.
肖婧  王兵 《水科学进展》2020,31(6):820-831
为研究黄土丘陵沟壑区多种因素对撂荒草地入渗特征的影响,采用野外自然降雨观测法,研究不同降雨特征(降雨量、平均雨强、降雨历时和最大30 min雨强(I30))、土壤前期含水量、坡长(10 m、20 m、30 m、40 m和50 m)和植被盖度条件下土壤入渗特征差异,通过灰色关联度法判断影响撂荒草地入渗特征的主导因子。结果表明:①入渗量随降雨量、降雨历时和I30增加而增大(R2>0.55,P < 0.01);入渗补给系数随降雨量、I30和平均雨强增大而减小(R2>0.12,P < 0.05);平均入渗率随降雨强度、I30增加而递增(R2>0.53,P < 0.01)。②入渗量和平均入渗率随前期含水量增加而减少,入渗补给系数随之增加而增大(R2>0.13,P < 0.05)。③入渗量、入渗补给系数和平均入渗率总体随坡长增加而增大(R2>0.56,P < 0.01),但在坡长30 m和40 m之间存在临界坡长。④在入渗效率较高的情况下,植被对土壤入渗的影响并不显著,降雨特征和坡长成为主导因子。  相似文献   

2.
肖婧  王兵 《水科学进展》2021,31(6):820-831
为研究黄土丘陵沟壑区多种因素对撂荒草地入渗特征的影响,采用野外自然降雨观测法,研究不同降雨特征(降雨量、平均雨强、降雨历时和最大30 min雨强(I30))、土壤前期含水量、坡长(10 m、20 m、30 m、40 m和50 m)和植被盖度条件下土壤入渗特征差异,通过灰色关联度法判断影响撂荒草地入渗特征的主导因子。结果表明:①入渗量随降雨量、降雨历时和I30增加而增大(R2>0.55,P<0.01);入渗补给系数随降雨量、I30和平均雨强增大而减小(R2>0.12,P<0.05);平均入渗率随降雨强度、I30增加而递增(R2>0.53,P<0.01)。②入渗量和平均入渗率随前期含水量增加而减少,入渗补给系数随之增加而增大(R2>0.13,P<0.05)。③入渗量、入渗补给系数和平均入渗率总体随坡长增加而增大(R2>0.56,P<0.01),但在坡长30 m和40 m之间存在临界坡长。④在入渗效率较高的情况下,植被对土壤入渗的影响并不显著,降雨特征和坡长成为主导因子。  相似文献   

3.
湖南辰溪孝坪煤矿桠杉坡井为岩充水煤矿井,采用跨越法采煤,辅以封闭突水点、废弃巷道、采空区和将矿坑水排泄补给浅部溶洞水,控制了矿坑涌水量,保持了地下水基本平衡,防止了矿坑疏干排水诱发岩溶地面塌陷。其成功经验可供借鉴。  相似文献   

4.
Large amounts of groundwater are discharged during underground mining operations. As a result, the drawdown of groundwater, known as aquifer dewatering, is common in mining areas. Because of variability in permeability between different media in mines, mine drainage occurs primarily as non-continuous flow. However, calculations of mine water yield are usually made based on the continuous flow theory, and therefore often produce erroneous results. This study predicts the water yield of a mine using the module MODFLOW and incorporating the non-continuous flow theory into the calculation. Using this method, the predicted water yield of a mine was approximately 50 % lower than that predicted using the continuous flow theory. The model also demonstrates that the rate of mine drainage varies over time; there is initially a decrease in the rate of drainage which gradually approaches a constant value. Double level flow occurs when there is non-continuous flow in continuous media, which can effectively minimize the influence of mine drainage on upper aquifers and relieve the conflict between groundwater supply and drainage in the mining area.  相似文献   

5.
考虑降雨入渗的有密集排水孔幕渗流场分析   总被引:3,自引:1,他引:2  
陈建余 《岩土力学》2005,26(1):150-154
有复杂边界面的渗流场求解问题经常会同时涉及降雨入渗边界和密集排水孔边界,这一般是一个非饱和渗流问题,因此传统的稳定饱和排水子结构模型不能适用。根据2类不同的排水孔,给出了排水子结构典型网格划分型式,提出了相应的非饱和排水子结构水力学模型,并引入传统模型中未考虑的降雨入渗等其它边界,使得模型更全面和完善。  相似文献   

6.
Flooded underground mines are attractive for groundwater heat pump systems, as the voids created during mining operations enhance the subsurface permeability and storage capacity, which allows the extraction of significant volumes of groundwater without requiring extensive drilling. Heat exchange at a flooded mine is, however, difficult to predict because of the complex geometry of the underground network of tunnels. A case study is presented here to demonstrate that numerical simulations of groundwater flow and heat transfer can help assess production temperatures required to optimize the design of a heat pump system that uses mine water. A 3D numerical model was developed for the Gaspé Mines located in Murdochville, Canada, where a district heating and cooling system is being studied. The underground mining tunnels and shafts are represented in the model with 1D elements whose flow and heat transfer contributions are superimposed to those of the 3D porous medium. The numerical model is calibrated to simultaneously reproduce the groundwater rebound that occurred when the mine closed and the drawdown measured during a pumping test conducted in a former mining shaft. Predictive simulations over a period of 50 years are subsequently performed to minimize pumping rate and determine maximum heat extraction rate.  相似文献   

7.
张作礼 《山东地质》2014,(10):39-41
厚煤层水淹区残余煤量的回收一直是衰老矿井所面临的一个重要课题,残余煤复采安全技术研究对资源枯竭的老矿井有着再生的作用并能够带来可观经济效益及社会效益。该文对水淹区残余煤量的复采方法进行了详细的研究,根据老空水的贮存及残余煤量的赋存状况,提出了一系列的方法和措施。通过合理疏放老空水、优化巷道布置和开采工艺设计,对原已搁弃的呆滞煤量进行了充分的回收,为类似条件下残余煤的回收提供了宝贵的意见。  相似文献   

8.
王泓博  张勇  庞义辉  贾伟 《岩土力学》2022,43(4):1073-1082
煤炭开采引起覆岩破断及地表下沉,覆岩及地表运移规律可反映裂隙带高度的动态演化过程。因地表下沉滞后于煤炭开采,对于废弃采空区,长期压实作用导致裂隙带高度较采动期间有所降低。基于地表点下沉速度的阶段特征将裂隙带高度的演化过程分为2个阶段,第1阶段裂隙带发育对应岩层破断逐步向上传递的过程,第2阶段裂隙带高度降低对应离层及裂隙闭合、断裂岩层受压后变形回弹及破碎岩体自然压实的过程。着眼于压实作用对裂隙带高度的影响,根据煤层采厚、垮落带和裂隙带岩层变形量及地表下沉值之间的定量关系,建立了第2阶段裂隙带高度预测模型,并结合太平煤矿实测结果进行验证,采用控制变量法分析了单一因素影响下废弃采空区裂隙带高度的演化特征。结果表明:废弃采空区裂隙带高度受控于垮落带块体强度、垮落带初始碎胀系数、采动期间裂隙带高度最大值及对应的垮落带高度、煤层埋深、地表最终下沉量等因素,太平煤矿采后15 a的裂隙带高度实测值11.36~13.00 m与理论预测值12.75 m吻合度较高,模型的可靠性得到验证。最后,应用此预测模型对武安煤矿(关停矿井)2002-2003年采空区裂隙带高度开展理论计算,结合地空瞬变电磁探测确定了地面瓦斯抽采钻孔理想的终孔位置并成功开展了地面钻孔瓦斯抽采试验。  相似文献   

9.
普阳煤矿位于一断陷盆地的浅部新近系地层中,矿区被3种类型的水文地质边界圈闭.煤层分布标高低于暗河出口100~230 m,煤田四周及盆地基底均为岩溶含水层,其承压水头高于煤层底板67~268 m,预计最低开采标高的平均承压水头约206 m.为解决矿区地下水突水威胁,监测普阳河水流入和流出的水量,根据水均衡原理及矿坑充水要...  相似文献   

10.
矿山内排土场因其储量大、结构松散和强度低等特点,在降雨条件下极易产生侵蚀或整体失稳破坏,因此降雨入渗分析对预测内排土场稳定性至关重要。以元宝山露天煤矿内排土场为原型,按相似试验理论进行物理模型试验,研究降雨入渗特征,根据试验结果对经典Green-Ampt入渗模型进行改进。结果表明:雨水入渗过程中,随着浸润锋的向下运移,坡面侵蚀由溅蚀凹槽开始,逐渐过渡为径流侵蚀,最后呈现为溯源侵蚀破坏,整体呈现平行于坡表面的浅层滑坡特征;浸润锋之上非饱和浸润层的存在,导致经典Green-Ampt模型计算结果不准确;在考虑浸润层厚度和累积入渗量基础上,推导出改进的Green-Ampt模型;改进后的Green-Ampt模型为分段函数,能够反映降雨入渗使坡面由非饱和向饱和过渡的实际特征。验证结果显示,使用改进模型,浸润锋入渗深度和累积入渗量的预测精度显著提升,虽然冲蚀破坏和初始含水率的差异导致降雨入渗后期的预测精度有所下降,但相关结果对煤矿内排土场降雨初期稳定性分析具有重要意义。改进后的Green-Ampt模型的计算结果与实测数据更为接近,能为分析露天煤矿内排土场降雨入渗规律及边坡稳定性研究提供参考。  相似文献   

11.
Turquoise Lake is a water-supply reservoir located north of the historic Sugarloaf Mining district near Leadville, Colorado, USA. Elevated water levels in the reservoir may increase flow of low-quality water from abandoned mine tunnels in the Sugarloaf District and degrade water quality downstream. The objective of this study was to understand the sources of water to Dinero mine drainage tunnel and evaluate whether or not there was a direct hydrologic connection between Dinero mine tunnel and Turquoise Lake from late 2002 to early 2008. This study utilized hydrograph data from nearby draining mine tunnels and the lake, and stable isotope (δ18O and δ2H) data from the lake, nearby draining mine tunnels, imported water, and springs to characterize water sources in the study area. Hydrograph results indicate that flow from the Dinero mine tunnel decreased 26% (2006) and 10% (2007) when lake elevation (above mean sea level) decreased below approximately 3004 m (approximately 9855 feet). Results of isotope analysis delineated two meteoric water lines in the study area. One line characterizes surface water and water imported to the study area from the western side of the Continental Divide. The other line characterizes groundwater including draining mine tunnels, springs, and seeps. Isotope mixing calculations indicate that water from Turquoise Lake or seasonal groundwater recharge from snowmelt represents approximately 10% or less of the water in Dinero mine tunnel. However, most of the water in Dinero mine tunnel is from deep groundwater having minimal isotopic variation. The asymmetric shape of the Dinero mine tunnel hydrograph may indicate that a limited mine pool exists behind a collapse in the tunnel and attenutates seasonal recharge. Alternatively, a conceptual model is presented (and supported with MODFLOW simulations) that is consistent with current and previous data collected in the study area, and illustrates how fluctuating lake levels change the local water-table elevation which can affect discharge from the Dinero mine tunnel without physical transfer of water between the two locations.  相似文献   

12.
以重庆松藻矿区在打通的一综采工作面缓倾斜地层中掘进时发生的两次顶板水灾为例,对其顶板突水原因进行了探讨。通过分析该矿区的矿井地质及水文地质条件,认为矿井充水水源为上覆地层的离层水。该矿井的M7-3煤层开采后,导水裂隙切穿了上覆地层长兴组灰岩,贯通了玉龙山一段灰岩隔水层,进入玉龙岩二段岩溶裂隙含水层。由于含水层的上覆岩层在采掘过程中,因岩性差异发生不均衡沉降,形成了大量的离层空间。离层空间吸收、储存的大量地表降雨在采掘工作面推进到一定位置时,就会发生突水。据估算,S1821工作面上覆岩体离层、裂隙储水空间按三分之一计算为2.064×105m^2,与该工作面抢险救灾期间排出的涌水量基本吻合。根据该矿离层水的赋存特点,提出了保证排水系统畅通,加强采煤设备管理,提高采面设计水平的防治水对策。  相似文献   

13.
废弃矿井地下水淹没过程的水流与水位数值模拟   总被引:1,自引:0,他引:1  
定量分析和研究废弃矿井淹没过程的水流特征对于预测和防止废弃矿井地下水淹没过程中诱发的次生灾害具有重要意义。建立了废弃矿井淹没的多种介质水流数学模型,得出了淹没补给水量随时间、矿井内淹没水位和补给水源含水层水位之间的相关关系,建立了淹没补给水量与相关影响因素之间的函数关系式,完成了矿井淹没过程中涌水量实时计算的FEFLOW模块设计和开发。进行了近水平煤层开采后废弃矿井充水淹没水位回弹过程的数值模拟计算,得到了不同充水介质在充水淹没过程中的水流和水位回弹特征。结果显示,FEFLOW二次开发模块运算效果良好,具有实用价值。   相似文献   

14.
东坪金矿赋存偏碱必杂岩体中,所处水文地质单元为低山分水岭近侧的基岩裂隙水区,东坪沟是矿区唯一的地表水体,地上水有第四系孔隙水和基岩裂隙水,矿床充水因素主要为地表水和第四系也隙水,其次为基岩裂隙水,基岩裂隙水直接渗漏到矿坑,地表水和第四系孔隙水通过基岩裂隙渗漏到矿坑,东坪金矿床属以基岩裂隙水直接充水,地表水和和纱孔隙之间接充水的水文地质条件中等类型的矿床。  相似文献   

15.
煤矿区地面瓦斯废弃井改造再利用,可进行采动区瓦斯抽采,具有保障回采工作安全生产,瓦斯资源有效利用,减少瓦斯逸散对环境压力等经济环保多重效益。针对这一目的,结合采动区地面井和废弃井的特点,提出废弃井“一井多用”瓦斯抽采技术思路。通过分析试验工作面开采工艺、覆岩结构及废弃井的基本情况等条件,研究并提出了废弃井优选及判识、地面井改造工艺、防护装置安设、抽采系统布置及抽采控制技术等,改进了废弃井改造射孔造缝段长度确定方法。研发了基于油套环空动态调节、组合套管双重防护及筛管分级优化的安全防护方法,形成了废弃井“一井多用”地面井瓦斯抽采技术。选取晋城矿区岳城煤矿作为试验对象,完成了3口废弃井(井号为YC-50、YC-52、YC-54)再利用改造试验,其地面井瓦斯抽采量累计分别为257.88万、172.50万、129.60万m3。YC-50井改造运行后,地面井抽采范围内工作面上隅角瓦斯体积分数最大值从0.77%降至0.40%,降幅48.05%;YC-52井改造运行后,采煤工作面上隅角瓦斯体积分数降幅为52.38%,有效保障了回采工作面安全生产,实现了废弃井“一井多用”目标,取得了良好的经济与社会效益...  相似文献   

16.
刘晓宇 《地下水》2019,(3):17-19,85
矿井采煤对地下水环境的影响主要为对具有供水意义的含水层水位及水量产生影响,确定采煤引起地下水水位降及漏失量是煤矿地下水环境影响评价的关键。以纳林河矿区某大型矿井为例,运用Visual MODFLOW建立模拟区地下水流数值模型,利用实测流场和长观孔的动态观测资料识别和验证数值模型,利用模型来预测采煤对第四系-白垩系含水层水位及水量的影响。模拟结果显示:前25年采煤引起地下水最大水位降为3.6 m,引起地下水的漏失量最大为141.87万m^3/a,占矿井涌水量的29.88%;利用矿化度法确定的越流量占矿井涌水量的6.39%~34.89%,模拟结果基本合理,可作为矿井采煤对地下水环境影响的研究依据。  相似文献   

17.
Osheepcheon Creek running through the Dogyae area is being polluted by the influx of the abandoned coal mine drainage. Generally, the more polluted water has lower pH and Eh and higher conductivity values. The concentrations of Mg, Ca, Fe, SO4, and some trace elements, such as Cd, Co, Cr, Mo, Ni, Pb, Rb, Sr, U and Zn, are tens to hundreds of times more concentrated in the abandoned coal mine drainage than in the unpolluted streamwater. However, most immobile toxic pollutants from the mine drainage are quickly removed from the streamwater by the precipitation of amorphous Fe hydroxide and sorption on the precipitated Fe hydroxide. The fast removal of the pollutants from the streamwater maintains the water quality of the creek as acceptable at most places along the stream path, except where the abandoned coal mine drainage flows in. However, the creek has the potential of deteriorating quickly if the mine drainage is allowed to be continuously combined with the streams. A function of pH, Eh, and conductivity has been developed with discriminant function analysis for the purpose of easy, fast, and inexpensive measurement of the degrees of pollution of the streams. The estimated pollution of the streams with the discriminant function are consistent with what the chemical compositions of the water samples indicate. The pollution map of the study area was constructed from the calculated scores with the discriminant function. The pollution map suggests that the pollutants mainly come from the west side of Osheepcheon Creek. Thus, the abandoned coal mine drainage from the west side has to be appropriately treated as soon as possible to prevent Osheepcheon Creek from being further polluted. Considering the topography, climate, and the amount of the mine drainage, an active treatment method is recommended.  相似文献   

18.
郭再峰 《探矿工程》2011,38(12):79-82
煤矿在开采煤炭的同时,会有大量的矿井污水排到地面,造成环境污染。为解决矿井水排放的污染问题,施工大口径回灌井和建造地面水净化处理厂,矿井水经处理后部分用于煤矿生产,多余部分通过回灌井注入地下,实现水资源循环利用和节能减排。通过梧桐庄矿工程实例,介绍了煤矿矿井水净化处理与回灌治理技术。  相似文献   

19.
晋煤集团赵庄矿3号煤层为高瓦斯煤层,瓦斯抽采难度大,存在煤与瓦斯突出的安全隐患,防治水方面还存在底板带压开采问题,严重制约了矿井安全高效生产。通过提出保护层开采方案,先期开采下伏8-1号薄煤层,释放3号煤层应力,增加煤层透气性,同时制定8-1号煤带压开采的防治水技术策略,最终实现了3号煤瓦斯安全疏放抽采,防治水工作顺利开展,对同时存在高瓦斯和承压水上采煤问题的类似矿井具有指导意义。   相似文献   

20.
露天煤矿开采过程中的矿坑疏排水是引起地下水资源流失的重要原因,寻求新的控水方法势在必行。以内蒙古赤峰市元宝山露天煤矿为研究对象,根据研究区水文地质与露天煤矿开发特征,分析了露天开采驱动下帷幕墙体建设对地下水系统控制的基本原理,得出帷幕墙体渗透能力越弱、厚度越大、与补给水体距离越近是帷幕墙减少露天采坑涌水的基本思路。将露天采矿疏排水与地下水系统数值仿真研究结合,对露天煤矿开采与帷幕墙建设对矿坑疏排水强度影响程度进行预测分析,模拟结果显示,采用针对主要涌水段的局部帷幕工程方案,地下水仍然以露天矿采坑为降落漏斗中心,区域流场形态基本未发生重大变化,在未帷幕区段地下水发生了强烈的侧向绕流现象,初期(300 d)矿坑残余涌水量较之现有矿坑排水量最大减幅 37.16%,而残余涌水量随时间增大趋势明显。按准全封闭型帷幕方案建墙后,地下水基本未发生绕流现象,矿井残余涌水量为先减小后增大的趋势,最大减幅达85.79%,且后期涌水量增加幅度不大,可见准封闭型帷幕建设方案较之局部帷幕方案对矿坑整体涌水量的减排作用显著。通过分析露天煤矿开采侧向帷幕控水规律,构建帷幕阻水条件下地下水系统仿真模型,评价帷幕截水减排效果,以期为露天矿区煤–水资源协调开发提供科学依据。   相似文献   

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