深部煤层大直径钻孔耗能防冲机理研究.pdf

分类号分类号 TD324 密密级级公公开开 U D C 622 单位代码单位代码 10424 学学位位论论文文深部煤深部煤层层大直径钻孔耗能防冲机理研究大直径钻孔耗能防冲机理研究王王俊俊申请学位级别申请学位级别博士学位博士学位专业专业名名称称采矿工程采矿工程指导教师姓名指导教师姓名蒋蒋金金泉泉职职称称教教授授山山东东科科技技大大学学二二〇〇一八一八年年六六月月万方数据国家自然科学基金项目（51574154）国家自然科学基金科学部主任基金（51344009）山东省重点研发计划（2018GSF116003）论文题目深部煤深部煤层层大直径钻孔耗能防冲机理研究大直径钻孔耗能防冲机理研究作者姓名王王俊俊入学时间 2015 年年 9 月月专业名称采矿工程采矿工程研究方向矿山压力矿山压力与与岩层岩层控制控制指导教师蒋蒋金金泉泉职称教教授授宁宁建建国国副副教教授授论文提交日期 2018 年年 6 月月论文答辩日期2018 年年 5 月月 30 日日授予学位日期 2018 年年 6 月月万方数据 STUDY ON THE ENERGY DISSIPATED MECHANISM OF LARGE-DIAMETER BOREHOLE FOR COALBURST CONTROL A Dissertation ted in fulfillment of the requirements of the degree of DOCTOR OF PHILOSOPHY from Shandong University of Science and Technology by Wang Jun Supervisor Professor Jiang Jin Quan Associate Professor Ning Jian Guo College of Mining and Safety Engineering June 2018 万方数据学位论文原创性声明学位论文原创性声明本人呈交给山东科技大学的这篇博士学位论文，除所列参考文献和世所公本人呈交给山东科技大学的这篇博士学位论文，除所列参考文献和世所公认的文献外，全部是本人攻读学位期间在导师指导下的研究成果。除文中已经认的文献外，全部是本人攻读学位期间在导师指导下的研究成果。除文中已经标明引用的内容外，本论文不包含任何其他个人或集体已经发表或撰写过的研标明引用的内容外，本论文不包含任何其他个人或集体已经发表或撰写过的研究成果。对本文的研究做出贡献的个人和集体，均已在文中以明确方式标明。究成果。对本文的研究做出贡献的个人和集体，均已在文中以明确方式标明。本人完全意识到本声明的法律结果由本人承担。本人完全意识到本声明的法律结果由本人承担。若有不实之处，本人愿意承担相关法律责任。若有不实之处，本人愿意承担相关法律责任。博士生签名博士生签名日日期期、、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山东科技大学有关保留、使用学位论文的规定，同意本人所本人完全了解山东科技大学有关保留、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。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，作为申请学位的条件之一，学校有权保留学位论文并向国家有关部门或其学校有权保留学位论文并向国家有关部门或其指定机构送交论文的电子版和纸质版；有权将学位论文的全部或部分内容编入指定机构送交论文的电子版和纸质版；有权将学位论文的全部或部分内容编入有关数据库发表，并可以以电子、网络及其他数字媒体形式公开出版；允许学有关数据库发表，并可以以电子、网络及其他数字媒体形式公开出版；允许学校档案馆和图书馆保留学位论文的纸质版和电校档案馆和图书馆保留学位论文的纸质版和电子版，可以使用影印、缩印或扫子版，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；为教学和科研目的，学校档案馆和图书馆描等复制手段保存和汇编学位论文；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。师生阅读、浏览。（保密的学位论文在解密后适用本授权）（保密的学位论文在解密后适用本授权）博士生签名博士生签名导师签名导师签名日日期期日日期期万方数据学位论文审查认定书学位论文审查认定书研究生研究生王王俊俊在规定的学习年限在规定的学习年限内，按照培养方案及个人培养内，按照培养方案及个人培养计划，完成了课程学习，成绩合格，修满规定学分；在我的指导下完成本学位计划，完成了课程学习，成绩合格，修满规定学分；在我的指导下完成本学位论文，论文中的观点、数据、表述和结构为我所认同，论文撰写格式符合学校论文，论文中的观点、数据、表述和结构为我所认同，论文撰写格式符合学校的相关规定，同意将本论文作为申请学位论文。的相关规定，同意将本论文作为申请学位论文。导师签名导师签名日日期期万方数据山东科技大学博士学位论文摘要 I 摘摘要要随着对煤炭资源需求量的增加和开采强度的不断加大，我国中、东部矿井逐步转向深部。深部矿井开采时，冲击地压发生的频率和强度愈加强烈，给煤矿安全生产带来巨大威胁，亟需深入研究冲击地压防治机理及技术。目前，大直径钻孔防冲技术以低扰动、快捷、方便等优点，被我国绝大多数冲击地压矿井所采用。但关于大直径钻孔卸压-耗能防冲机理以及不同冲击危险区域如何定量设计大直径钻孔防冲参数（钻孔直径、长度和间距等）还需深入研究。鉴于此，本文采用室内实验、数值模拟、理论分析和现场监测等研究方法，研究大直径钻孔煤体破裂机制，掌握大直径钻孔能量耗散演化规律，揭示大直径钻孔防治冲击地压机理；并结合深部工作面能量与冲击地压危险区分布特征，初步提出大直径钻孔布置参数定量设计方法。论文主要研究内容及获得的研究成果如下（1）基于煤体常规三轴、三轴加卸载实验及声发射实验，研究了不同围压下煤体应力-应变曲线、体积应变-轴向应变曲线、峰值轴向应变及最大体积应变等曲线变化规律，结合不同围压作用下煤体声发射特征以及耗散能演化特征，获得了不同围压下煤体失稳破坏能量阈值，并建立了煤体失稳破坏能量阈值与最小主应力的关系式。（2）建立了能够等效描述采空区矸石压实承载力学特性及应力恢复的数值模型，并针对新河煤矿 5302 工作面开采及地质赋存条件，仿真模拟研究了工作面推进过程中采动空间弹性应变能分布特征，揭示了采动能量的动态演化规律，并结合煤体失稳破坏能量阈值，划分了5302工作面采动空间冲击地压危险区域。（3）研究了大直径钻孔煤体裂纹起裂、汇聚至钻孔塌孔过程中，钻孔轴向及径向能量场演化规律，探讨了煤体强度、钻孔直径、侧压系数及煤体压力等因素对大直径钻孔煤体应力调整及能量耗散的影响，分析了钻孔间距和钻孔长度等因素对工作面弹性应变能的影响。（4）将大直径钻孔分为孔壁段和孔底两部分，利用断裂力学与弹塑性力学等，分别获得了钻孔塌孔区与塑性区边界解析表达式；基于能量耗散理论，获得了钻孔塌孔区与塑性区耗散能解析式，引入了能量耗散效率（钻孔耗散能与万方数据山东科技大学博士学位论文摘要 II 钻孔前煤体弹性应变能之比）的概念，探讨了煤体压力、煤体强度、钻孔直径，钻孔间距和钻孔长度等因素对能量耗散效率的影响，最终揭示了大直径钻孔防治冲击地压机理。（5）在揭示大直径钻孔防治冲击地压机理的基础上，结合深部工作面能量与冲击地压危险区分布特征，提出了大直径钻孔布置参数（钻孔长度、间距及直径等）定量设计方法，并用于新河 5302 工作面大直径防冲设计，现场工程实践表明所设计的大直径钻孔布置参数，降低了煤体应力或弹性应变能集中程度，实现了防冲效果。关键词关键词冲击地压；能量阈值；冲击危险性；大直径钻孔防冲；钻孔设计万方数据山东科技大学博士学位论文摘要 III Abstract In china, since the shallow coal resource is exhausted at some coalfields with each passing day, deep coal resources developing is extremely urgent to meet energy demand. In deep coal mining, the frequency and intensity of the coalburst is more intense, which brings great threat to the safety of coal mine production. Therefore, it is necessary to make a comprehensive study on the prevention and control of rockburst. At present, owing to the advantages of low disturbance, shortcut, convenience and so on, the largar-diameter borehole is used to prevent the harzard of coalburst in most coalburst-threaten coal mines. Actually, the academic community has reached a consensus on the energy relief effect of largar-diameter borehole. However, the energy dissipation mechanism of largar-diameter borehole for coalburst mitigation have not been studied, and it is still based on numerical simulation and engineering analogy to design layout parameter of largar-diameter borehole borehole length, diameter and spacing etc.. Aa a result, some coalburst-threaten coal mine still has the coalburst hazard after the implementation of the large diameter borehole. For this reason, laboratory test, theoretical analysis, numerical simulation, theoretical analysis and field moitoring s are used to research the failure mechanism of largar-diameter borehole, and study its energy dissipation evolution law, and then reveal the mechanism of largar-diameter borehole for coalburst mitigation. Finally, quantitative design of largar-diameter borehole parameter for coalburst mitigation is introduced. The main research contents and achievements are as follows 1 Conventional and cyclic loading–unloading triaxial compression tests and acoustic-emission experiments were carried out for coal specimens to study the influence of confining pressure on the stress–strain relations, volume strain-axial strain curve, peak axial strain and Maximum volume strain. On the basis of understanding of AE features, and energy evolution characteristics, the early-warning critical energy for coalburst assessment was introduced. The point at which the axial stress 86.23 of the peak strength indicates an increase in the risk of coal instability. The corresponding elastic strain energy accumulated within the coal can be regarded as a precursor to coalburst. Accordingly, a fitting ula is presented to predict the early-warning critical energy for brittle coal subject to different minimum principal stress. 2 Considering the goaf compression and stress recovery, a numerical model was built and verified using a simulation case study. According to the mining and geological conditions of longwall face 5302 in Xinhe coal mine, the redistribution of mining-induced energy during the advancing of longwall face was study, and revealed the dynamic evolution law of the mining-induced energy. Combinated the 万方数据山东科技大学博士学位论文摘要 IV early-warning critical energy and redistribution of mining-induced energy, the distribution of coalburst-prone zone around longwall face 5302 was discussed. 3 In order to investigate the failure process of largar-diameter borehole, the particle simulation was used in numerical simulations to discuss crack propagation, microcrack distribution. Then, dynamic failure process of largar-diameter borehole and time-space evolution of energy around longface face induced by borehole failure. The influence of coal mass strength, borehole diameter, side pressure coefficient and pressure on the borehole failure and stress adjustment was discussed, and the effect of borehole spacing and length on the distribution of energy was analysed. 4 A single large-diameter borehole was divided into two parts borehole wall and borehole bottom. Using fracture mechanics and elastoplastic mechanics, etc., the borehole collapse zone and plastic zone radiu of the borehole wall and borehole bottom were analytical obtained and verified with simulation study. Based on the theory of energy dissipation, dissipative energy of the borehole collapse zone and plastic zone were also analytical obtained, and energy dissipation efficiency was introduced to discuss the influence of coal mass strength, borehole diameter, pressure, borehole spacing and length on the energy dissipation efficiency. Finally, the mechanism of largar-diameter borehole for coalburst mitigation was revealed. 5 On the basis of understanding of the mechanism of largar-diameter borehole for coalburst mitigation, the redistribution of mining-induced energy and the distribution of coalburst-prone zone, quantitative design of largar-diameter borehole parameter for coalburst mitigation was introduced, which was used to design largar-diameter borehole layout parameters borehole length, diameter and spacing etc. for mitigation of coalburst in longwall 5302 of xinhe coal mine. Field practice showed that the designed largar-diameter borehole reduced the stress or energy concentration, and mitigation of coalburst reached a certain effect. Keywords coalburst; early-warning critical energy; coalburst-prone zone; largar-diameter borehole coalburst mitigation; borehole designment 万方数据山东科技大学博士学位论文目录 V 目目录录摘摘要要 ....................................................................................................... I 目目录录 ...................................................................................................... V 1 绪绪论论 ................................................................................................... 1 1.1 研究背景及意义 ............................................................................. 1 1.2 国内外研究现状 ............................................................................. 2 1.3 存在的问题及不足 ........................................................................ 10 1.4 主要研究内容及技术路线 ............................................................. 11 2 不同围压不同围压条件下煤体失稳破坏能量阈值条件下煤体失稳破坏能量阈值实实验研究验研究 ...................... 14 2.1 引言 ........................................................................................................... 14 2.2 煤样常规三轴加压、循环加卸载实验 ................................................... 15 2.3 常规三轴下煤体变形及声发射特征 ....................................................... 19 2.4 受载煤体失稳破坏能量演化规律 ........................................................... 26 2.5 煤体失稳破坏能量阈值 ........................................................................... 31 2.6 本章小结 ................................................................................................... 34 3 深井综放工作面采动应力及能量场时深井综放工作面采动应力及能量场时-空演化规律空演化规律 ..................... 35 3.1 引言 ........................................................................................................... 35 3.2 工作面概况与监测方案 ........................................................................... 35 3.3 深井综放工作面采动应力分布特征 ....................................................... 39 3.4 5302工作面采动能量场时-空演化规律 .................................................. 44 3.5 5302工作面冲击地压危险性分析 ........................................................... 61 3.6 本章小结 ................................................................................................... 63 4 大直径钻孔煤体破坏能量耗散与转移规律研究大直径钻孔煤体破坏能量耗散与转移规律研究 .......................... 65 4.1 颗粒流数值模型的建立 ........................................................................... 65 万方数据山东科技大学博士学位论文目录 VI 4.2 钻孔煤体破裂机制 ................................................................................... 69 4.3 钻孔煤体破裂的影响因素分析 ............................................................... 71 4.4 大直径钻孔对工作面能量分布的影响研究 ........................................... 79 4.5 本章小结 ................................................................................................... 86 5 深部煤深部煤层大直径钻孔耗能防冲机理研究层大直径钻孔耗能防冲机理研究....................................... 87 5.1 引言 ........................................................................................................... 87 5.2 大直径钻孔破坏理论解析 ....................................................................... 87 5.3 大直径钻孔变形破坏过程中的能量分析 ............................................... 98 5.4 大直径钻孔能量耗散分析 ..................................................................... 105 5.5 深井工作面大直径钻孔防冲机理 ......................................................... 111 5.6 本章小结 ................................................................................................. 113 6 工程应用工程应用 ......................................................................................... 114 6.1 引言 ........................................................................................................... 114 6.2 大直径钻孔布置参数设计方法 ............................................................... 114 6.3 现场工程应用实验 ................................................................................... 115 6.4 大直径钻孔防冲效果检验 ....................................................................... 118 6.5 本章小结 ................................................................................................... 122 7 结论与展望结论与展望 ..................................................................................... 123 7.1 主要结论 ................................................................................................... 123 7.2 创新点 ....................................................................................................... 125 7.3 展望 ........................................................................................................... 125 参考文献参考文献 ............................................................................................... 126 致致谢谢 ............................................................................................... 143 科研学习经历及攻读博士期间的主要成果科研学习经历及攻读博士期间的主要成果 ....................................... 145 万方数据山东科技大学博士学位论文目录 VII Content Abstract .................................................................................................. I Content .................................................................................................. V 1 Introduction .......................................................................................... 1 1.1 Brackground and significance ..................................................................... 1 1.2 Problem statements ...................................................................................... 2 1.3 Existing problems and shortcomings ......................................................... 10 1.4 Main research contents and thesis outline ................................................. 11 2 Identification of early-warning critical energy to uate coal sample failure considering the effect of confining pressure ....... 14 2.1 Introduction .....................................................................