孔内直流电法探测煤层底板破坏深度研究.pdf

工程硕士学位论文 孔内直流电法探测煤层底板破坏深度研究 Study on the Depth of Coal Seam Floor Failure Detected by Direct Current Resistivity in Borehole 作 者李少华 导 师刘树才教授 中国矿业大学 2019 年 5 月 万方数据 学位论文使用授权声明学位论文使用授权声明 本人完全了解中国矿业大学有关保留、使用学位论文的规定，同意本人所撰 写的学位论文的使用授权按照学校的管理规定处理 作为申请学位的条件之一， 学位论文著作权拥有者须授权所在学校拥有学位 论文的部分使用权，即①学校档案馆和图书馆有权保留学位论文的纸质版和电 子版，可以使用影印、缩印或扫描等复制手段保存和汇编学位论文；②为教学和 科研目的，学校档案馆和图书馆可以将公开的学位论文作为资料在档案馆、图书 馆等场所或在校园网上供校内师生阅读、浏览。另外，根据有关法规，同意中国 国家图书馆保存研究生学位论文。 （保密的学位论文在解密后适用本授权书） 。 作者签名 导师签名 年 月 日 年 月 日 万方数据 II 中图分类号 学校代码 10290 UDC 密 级 公开 中国矿业大学 工程硕士学位论文 孔内直流电法探测煤层底板破坏深度研究 Study on the Depth of Coal Seam Floor Failure Detected by Direct Current Resistivity in Borehole 作 者 李少华 导 师 刘树才 申请学位 工程硕士专业学位 培养单位 资源学院 学科专业 地质工程 研究方向 地球物理学 答辩委员会主席 评 阅 人 二○一九年四月 万方数据 致谢致谢 我已工作多年，自 2005 年始攻读工程硕士，期间由于工作调动等种种原因 无法静下心来完成我的毕业论文， 使得工程硕士时间已十余年之久， 终于在 2017 年年底下定决心要结束我的硕士生活，完成我成为硕士的一个梦想。我结合自己 在矿上工作多年的经验，根据矿上工作需求，在刘树才教授的悉心指导和热忱帮 助下，终于于今年年初完成了我论文初稿。回想这一年多的时间，为了完成工程 试验工作，与单位沟通选择可用工作面，设计钻孔位置和参数，长达近两个月的 数据采集，让我受益匪浅。另外，由于理论较为薄弱，进行数值模拟部分研究时 从头抓起，进展较慢，庆幸的是，我来到了一个很好的环境里，在这里有很多的 良师和益友，在论文编写和平时生活中给了我很多的指引和帮助，使我能够顺利 的完成论文。 本文在论文选题、研究思路、论文框架设计到最终的完稿，自始至终都得到 了我的导师刘树才教授的悉心指导和热忱帮助。刘老师严谨求实的学风、活跃的 思维和开阔的视野以及谦虚低调的生活态度，都深深的影响了我，终身难忘。值 此论文完成之际，谨向刘老师致以崇高的敬意和最诚挚的感谢。 特别感谢刘盛东教授，在进行工程试验时，是刘盛东老师提供的网络并行电 法仪器进行了数据采集工作，并为我的试验方案提供了指导工作。感谢孙亚军教 授、徐智敏副教授在水文地质背景调查和钻孔设计中的帮助。感谢博士杨海平、 李毛飞等， 感谢硕士高彬、 尹志贤、 杨冶、 童雪瑞等在数值模拟方面提供的帮助。 还有很多好友在此不一一提名，感谢他们在我学习和生活中的帮助与照顾。 非常感谢家人对我学业的支持和鼓励， 感谢他们在我的一些人生选择上给予 的建议与尊重，更多自由的选择自己的生活。 万方数据 I 摘摘 要要 煤炭安全开采一直备受社会各界的关注， 其中突水灾害作为煤矿重大灾害之 一，尤其是底板承压水经常造成经济、人员等重大损失。当煤层工作面开始回采 时， 势必对工作面底板岩石造成破坏， 使其电性发生变化， 底板隔水层厚度降低， 若无法确定剩余隔水层厚度能否承受底板承压水的压力， 将会对工作面正常回采 造成严重影响。直流电阻率法主要反应地下岩、矿石的电性信息，而钻孔一般与 目标体距离较近，本文结合直流电阻率法特点与钻孔距离目标体近的优点，提出 了一种通过钻孔进行直流电法探测从而确定煤层破坏深度的方法。 该方法是在钻 孔内布设供电电极和接收电极， 在工作面回采前进行一次数据采集并计算视电阻 率，通过回采不同程度时探测到的视电阻率与初始视电阻率获得视电阻率变化 率，结合视电阻率、视电阻率变化率以及数据采集时每个电极位置的电流变化情 况进行工作面底板破坏深度的确定。 本文首先通过数值模拟，分别对高阻、低阻底板破坏带的直流电法探测结果 特征进行分析， 通过视电阻率变化率计算公式得出不同电性的底板破坏带视电阻 率变化率特征， 得出以下结果 高阻底板破坏带的视电阻率变化率形态较为复杂， 随着回采工作面的推进，在其前方和下方形成变化率闭合等值线；低阻底板破坏 带的视电阻率变化率形态较为简单，当底板下方电阻率一致时，视电阻率变化率 极大值处于底板破坏带中心位置，当底板下方电阻率为高-低-高-低状态时，较薄 的底板破坏带视电阻率变化率极大值出现在破坏带下方边界， 对于较厚底板破坏 带视电阻率极大值出现在破坏带位置。 随后选取某矿区准备回采的工作面通过网络并行电法仪采集电流数据和电 位数据， 通过采集到的数据计算视电阻率以及视电阻率变化率， 绘制电流断面图、 视电阻率断面图和视电阻率变化率断面图，结合三种数据综合分析底板破坏深 度。与传统直流电法相比，孔内直流电法采集到的电流变化情况、视电阻率及视 电阻率变化率的综合解释对底板破坏厚度具有更高的分辨能力。 该论文有图 75 幅，表 4 个，参考文献 90 篇。 关键关键词词底板破坏带；孔内直流电法；网络并行电法；视电阻率变化率 万方数据 II Abstract The safety of coal mining has always been concerned by all sectors of society, among which water inrush disaster is one of the major disasters in coal mine, which causes great economic and personnel losses, especially the floor pressure area. It will cause rocky damage of working face floor, the electrical property will be changed and the thickness of floor water-proof layer will be reduced when the working face of coal seam begins to be mined. So, if it cannot determine the thickness of water-proof layer whether can withstand the pressure of floor confined water, it will cause serious impact on the normal mining of working face. The dc resistivity mainly reflects the electrical ination of underground rocks and ores, while the borehole is generally close to the target body. In this paper, combined with the advantages of the dc resistivity and borehole, a dc resistivity in the borehole is proposed to detect the depth of coal seam failure. The supply and receiving electrodes are arranged in the borehole and a data is acquired before the working face mining and calculating the apparent resistivity. The apparent resistivity change rate is obtained by detecting the apparent resistivity which under the different degrees of mining and the initial apparent resistivity. Combine the apparent resistivity, apparent resistivity change rate and the change of current data which collected by each electrode to determine the depth of working face floor fracture zone. Firstly, through the numerical simulation, analysis the detection results characteristic by direct current of high and low resistivity of working face floor fracture zone. The apparent resistivity change rate characteristic is got by the ula, and get the results the apparent resistivity change rate of high resistivity fracture zone of working face is relatively complex, change rate closed contour are ed in the front and bottom of fracture zone of working face with the mining working face advancing; the apparent resistivity change rate of low resistivity fracture zone of working face is relatively simple, the maximum apparent resistivity change rate on the center of the fracture zone when the resistivity of floor beneath is consistent, the maximum apparent resistivity change rate in the bottom boundary of thinner fracture zone and the maximum apparent resistivity change rate in the center of thicker fracture zone when the resistivity under the floor is high-low-high-low state. Then, selecting a preparation of mining working face and acquiring current and 万方数据 III potential data by network parallel electrical instrument. And changing the potential data to apparent resistivity and apparent resistivity change rate. Later, cross section profile of current, apparent resistivity and apparent resistivity change rate are drawn. Combining with the three kinds of data to comprehensive analysis the depth of working fracture zone. Comparing with the traditional DC , the joint interpretation of current variation, apparent resistivity and apparent resistivity change rate which collected by DC in the borehole has the higher resolution for the thickness of working face floor fracture zone. Keywords floor fracture zone; DC in borehole; network parallel electricity; rate of apparent resistivity change 万方数据 IV 目目 录录 摘摘 要要 .............................................................................................................................................. I 目目 录录 ........................................................................................................................................... IV 图清单图清单 ........................................................................................................................................ VIII 表清单表清单 .......................................................................................................................................... XII 变量注释表变量注释表................................................................................................................................. XIII 1 绪论绪论 .............................................................................................................................................1 1.1 研究背景及意义 .............................................................................................. 1 1.2 国内外研究现状 .............................................................................................. 2 1.3 本文研究的主要内容 ...................................................................................... 7 1.4 论文的组织结构 .............................................................................................. 8 2 基本原理基本原理 ....................................................................................................................................9 2.1 底板采掘破坏带探测基本原理 ...................................................................... 9 2.2 矿井直流电法三维正演 ................................................................................ 11 2.3 本章小结 ........................................................................................................ 15 3 钻孔电阻率法数值模拟钻孔电阻率法数值模拟 ......................................................................................... 16 3.1 均匀背景模型设计 ........................................................................................ 16 3.2 均匀背景模型模拟结果及分析 .................................................................... 17 3.3 均匀背景模型视电阻率变化率分析 ............................................................ 19 3.4 层状模型设计 ................................................................................................ 21 3.5 层状模型模拟结果及分析 ............................................................................ 22 3.6 层状模型视电阻率变化率分析 .................................................................... 27 3.7 本章小结 ........................................................................................................ 32 4 工程试验工程试验 ................................................................................................................. 34 4.1 矿区背景 ........................................................................................................ 34 4.2 监测钻孔设计 ................................................................................................ 34 4.3 数据采集 ........................................................................................................ 40 4.4 钻孔内监测数据处理与分析 ........................................................................ 41 4.5 本章小结 ........................................................................................................ 50 5 结论与展望结论与展望 ............................................................................................................. 51 万方数据 V 5.1 结论 ................................................................................................................ 51 5.2 展望 ................................................................................................................ 51 参考文献参考文献 ..................................................................................................................... 53 作者简历作者简历 ..................................................................................................................... 58 学位论文原创性声明学位论文原创性声明 ................................................................................................. 59 学位论文数据集学位论文数据集 ......................................................................................................... 60 万方数据 VI Contents Abstract ............................................................................................................................................ I Contents ........................................................................................................................................ IV List of Figures ............................................................................................................................ VIII List of Tables ................................................................................................................................ XII List of Variables ......................................................................................................................... XIII 1 Introduction ..............................................................................................................................1 1.1 Research Background ....................................................................................... 1 1.2 The Domestic and Foreign Research Situation ............................................... 2 1.3 Main Research Contents ................................................................................... 7 1.4 Organization Structure ...................................................................................... 8 2 Basic Principle ..........................................................................................................................9 2.1 Basic Principle of Detection of floor failure zone of coal seam ....................... 9 2.2 Three-dimensional Forward Modeling of Mine Direct Current ........ 11 2.3 Summary ......................................................................................................... 15 3 Numerical Simulation of Borehole Resistivity ....................................... 16 3.1 Design of Uni Background Model .......................................................... 16 3.2 Simulation Results and Analysis of Uni Background Model .................. 17 3.3 Analysis of Apparent resistivity Rate of Change of Uni Background Model .................................................................................................................... 19 3.4 Design of Strati Model ............................................................................ 21 3.5 Simulation Results and Analysis of Strati Model.................................... 22 3.6 Analysis of Apparent resistivity Rate of Change of Strati Model ........... 27 3.7 Summary ......................................................................................................... 32 4 Engineering Test ...................................................................................................... 34 4.1 Mining Area Background ................................................................................ 34 4.2 Monitoring Borehole Design .......................................................................... 34 4.3 Data Acquisition .............................................................................................. 40 4.4 Processing and analysis of borehole monitoring data ..................................... 41 万方数据 VII 4.5 Summary ......................................................................................................... 50 5 Conclusions and Prospects ..................................................................................... 51 5.1 Conclusions ..................................................................................................... 51 5.2 Prospectsshiwang .......................................................................................... 51 参考文献参考文献 ..................................................................................................................... 53 作者简历作者简历 ..................................................................................................................... 58 学位论文原创性声明学位论文原创性声明 ................................................................................................. 59 学位论文数据集学位论文数据集 ......................................................................................................... 60 万方数据 VIII 图清单图清单 图序号 图名称 页码 图 1-1 技术路线图 8 Figure 1-1 Technology roadmap 8 图 2-1 孔内电法成像工作示意图 10 Figure 2-1 Schematic diagram of electrical imaging in hole 10 图 2-2 有限差分矩形网格剖分示意图 14 Figure 2-2 The diagram of finite difference rectangular mesh subdivision 14 图 2-3 矿井直流电法三维正演有限差分程序流程图 15 Figure 2-3 The flow chart of finite difference 3D forward program of mine direct current 15 图 3-1 数值模拟地电模型 17 Figure 3-1 Geoelectric model of numerical simulat