工作面开采正断层活化规律及采动应力演化特征.pdf
分类号分类号TD324 TD324 密密 级级 公公 开开 U D CU D C 单位代码单位代码 1042410424 学学 位位 论论 文文 工作面开采正断层活化规律及采动应力工作面开采正断层活化规律及采动应力 演化特征演化特征 高高 琳琳 申请学位级别申请学位级别硕士学位硕士学位 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 二零一七年二零一七年六六月月 万方数据 论文题目论文题目 工作面开采正断层活化规律及采动应力演工作面开采正断层活化规律及采动应力演 化特征化特征 作者姓名作者姓名 高高 琳琳 入学时间入学时间 2014 年年 9 月月 专业名称专业名称 采矿工程采矿工程 研究方向研究方向 矿山压力及其控制矿山压力及其控制 指导教师指导教师 蒋蒋 金金 泉泉 职职 称称 教教 授授 论文提交日期论文提交日期2017 年年 4 月月 论文答辩日期论文答辩日期2017 年年 6 月月 授予学位日期授予学位日期2017 年年 6 月月 万方数据 Normal fault activation laws and mining stress evolution characteristics of working face mining A Dissertation ted in fulfillment of the requirements of the degree of MASTER OF PHILOSOPHY from Shandong University of Science and Technology by Gao Lin Supervisor Professor Jiang Jinquan College of Natural Resources and Environmental Engineering June 2017 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硕士学位论文,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硕士学位论文,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。 硕士生签名硕士生签名 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子版,可以使用影印、缩印或扫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 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) 硕士生签名硕士生签名 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 在规定的学习年限内,按照培养方案及个人培养计划,在规定的学习年限内,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论文,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的相关论文中的观点、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。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 山东科技大学硕士学位论文 摘要 I 摘摘 要要 断层是煤矿开采中常见、影响较大的地质构造。断层破坏了岩层连续整体 赋存状态,在其附近应力分布异常,采动效应十分突出,极易诱发动力灾害, 对煤矿开采设计、安全生产等存在重大影响。 本文通过理论计算、相似材料模拟试验和数值模拟方法,对上、下盘工作 面过正断层开采期间的断层两盘运移规律、采动应力演化特征和断层活化规律 进行研究,并通过现场微震事件进行了验证,主要研究成果如下 1)断层带切割了顶底板岩层的完整性,采动应力的阻隔效应显著,致使 断层煤柱易形成较高的应力集中区;下盘向正断层推进时,存在支承应力突增 点,使断层煤柱发生塑性破坏,释放大量弹性能;上盘向正断层推进时,支承 应力平缓增加,且推进过程中部分应力能够向下盘转移。相比上盘开采,下盘 开采时断层附近基本顶不易形成稳定铰接结构,向对盘传递载荷的能力弱,断 层阻隔作用相对较强,断层煤柱内支承应力存在突增现象。 2)断层面应力变化具有明显的时空特性。高位断层更容易受采动影响, 断层面应力状态首先发生改变。同一层位断层面上,剪应力与法向应力受采动 影响的敏感性不同,法向应力最先受到影响,随后剪应力发生改变。 3)由数值模拟和相似材料模拟可知,下盘工作面过正断层前后 30m,断 层活化危险性最大,两盘覆岩运动最剧烈,过断层期间下盘易沿断层面整体滑 移,过断层后 2030m 期间上盘悬臂基本顶易整体切落。上盘工作面过断层期 间及过断层后 20m 范围内断层活化的危险性最大,过断层后 70m 范围内两盘 覆岩运动最剧烈,直接顶和基本顶随采随冒,由工作面煤壁斜向断层周期性形 成破断线,切割下盘岩层,形成三角岩体,整体沉降。 4)随工作面向断层推进,高位断层首先受采动影响,而后在垂直方向上 向断层两端扩展。相比上盘开采,下盘工作面采动应力存在突增点,断层活化 启动时间较早,断层活化期间两盘运动更剧烈,活化危险性和危害性更大。 5)断层倾角、采高对煤壁前方采动应力和断层活化影响较大, 断层落差 影响较小。 关键词关键词 正断层;覆岩运动;采动应力;活化规律 万方数据 山东科技大学硕士学位论文 ABSTRACT I Abstract Faults are the most common causes and have larger influenced geological structure in Chinese coalmines. Due to the discontinuity of the rocks cut by the fault, the distribution of the mining stress is abnormal and the mining effect shows notable which would easily induced the dynamic disasters and has a great influence on design and safe production of the coalmine. The evolutionary laws of the roof subsidence of the two fault walls, mining stress and the fault activation affected by the mining operations with the working face on footwall or hanging wall passing through a normal fault can be studied utilizing theoretical calculation, physical simulation and the numerical simulation, he results of the numerical simulation are verified via the engineering case of the microseismic events. The results can be verified via the engineering case of the microseismic events. Hence, the main findings of the study are shown as fallows 1 When the working face in the footwall or the hanging wall advances toward the normal fault, the peak value of the front abutment stress rises gradually with the decreasing of the fault coal-pillar; and then the peak value would reduces due to the plastic failure of the coal pillar with the strength exceeding the ultimate strength. When the hanging wall mining, the stable structure of the main roof is easier ed than that of the footwall and the block effect of the fault is not obvious relatively due to the good capability of the loading transmission from the hanging wall, while the block effect of the fault is notable and the sudden increase of the abutment stress occurs when the footwall mining. 2 The stress variation of the fault plane has the notable spatiotemporal characteristics. The stress of the high-located fault plane would change firstly affected by the mining operations easily; the sensitivity of the shear stress and the normal stress is different at same point of the fault plane, of which the normal stress is first to be affected, and then the shear stress changes. 3 From the numerical simulation and the physical simulation, it can be concluded that when the working face in the footwall passes through the fault, the possibility of the fault activation is highest in the range of the -3030m which results from the violent movement of the overlying strata of the two fault walls; therein, the footwall strata is easily global 万方数据 山东科技大学硕士学位论文 ABSTRACT II slip along the fault plane while the main roof of the hanging wall is more easily cutting globally during the range of -20-30m. When the working face in the hanging wall passes through the fault, the possibility of the fault activation is highest in the range of the -200m and the violent movement of the overlying strata with -700m; The breaking line of the overlying strata develops to the fault obliquely and links up with the fault plane, the rock burst is easily induced due to the break of the footwall strata. 4 Along with the advance of the fault, the high fault is affected by mining at first, and then extends to the ends of the fault in the vertical direction. Compared with the fault surface of the upper wall, the sudden increase of the abutment stress occurs when the footwall mining, fault activation start time is earlier and the two plate movement is more severe, so the risk is bigger. 5 The mining stress and fault activation are affected notably by the dip angle of the fault and mining thickness of the coal seam, while the fall height is not obvious. Keywords normal fault, movement of overlying strata, mining stress, fault activation 万方数据 山东科技大学硕士学位论文 目录 Ⅰ 目目 录录 摘摘 要要 ⅠⅠ 目目 录录IIII 1 绪绪 论论1 1.1 课题的提出及研究意义„„„„„„„„„„„„„„„„„„„„„1 1.2 国内外研究现状„„„„„„„„„„„„„„„„„„„„„„„„ 2 1.3 主要研究内容和方法„„„„„„„„„„„„„„„„„„„„„„ 6 2 断层阻隔效应及断层活化力学分析断层阻隔效应及断层活化力学分析8 2.1 断层基本要素及分类„„„„„„„„„„„„„„„„„„„„„„ 8 2.2 正断层应力阻隔效应研究„„„„„„„„„„„„„„„„„„„„10 2.3 断层活化理论基础„„„„„„„„„„„„„„„„„„„„„„„13 2.4 本章小结„„„„„„„„„„„„„„„„„„„„„„„„„„„17 3 正断层采场覆岩运动规律的相似模拟研究正断层采场覆岩运动规律的相似模拟研究18 3.1 相似材料模拟试验设计„„„„„„„„„„„„„„„„„„„„„ 18 3.2 正断层采场覆岩演化规律研究„„„„„„„„ „„„„„„„„„„ 23 3.3 本章小结„ „„„„„„„„„„„„„„„„„„„„„„„„„„ 36 4 正断层采动应力演化与断层活化特征正断层采动应力演化与断层活化特征 38 4.1 FLAC3D 模拟软件简介„„„„„„„„„„„„„„„„„„„„„ 38 4.2 数值模型及模拟方案„„„„„„„„„„„„„„„„„„„„„„ 38 4.3 过正断层开采采动应力演化特征„„„„„„„„„„„„„„„„„ 42 4.4 正断层活化规律研究„„„„„„„„„„„„„„„„„„„„„„ 50 4.5 不同因素对采动应力及断层活化影响„„„„„„„„„„„„„„„ 57 4.6 本章小结„„„„„„„„„„„„„„„„„„„„„„„„„„„ 62 万方数据 山东科技大学硕士学位论文 目录 Ⅰ 5 工程实例验证工程实例验证64 5.1 微震理论基础„„„„„„„„„„„„„„„„„„„„„„„„„ 64 5.2 东滩煤矿 14310 工作面微震监测„„„„„„„„„„„„„„„„„ 66 5.3 鲍店煤矿 103下03 工作面微震监测„„„„„„„„„„„„„„„„ 67 5.4 本章小结„„„„„„„„„„„„„„„„„„„„„„ „„„„„72 6 主要结论主要结论75 参考文献参考文献76 致致 谢谢 81 攻读硕士期间攻读硕士期间主要主要成果成果82 万方数据 山东科技大学硕士学位论文 Contents III Contents 1 Exordium„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„ 1 1.1 Research background and significance of the project „„„„„„„„„„„„1 1.2 Research status at home and abroad „„„„„„„„„„„„„„„„„„2 1.3 Main research contents and s „„„„„„„„„„„„„„„„„ 6 2 Mechanics Analysis of Fault Barrier Effect and Fault Activation „„„„„„„„8 2.1 Basic fault elements and classification „„„„„„„„„„„„„„„„ 8 2.2 Study on barrier effect of fault on mining stress„„„„„„„„„„„„„ 10 2.3 Theoretical basis of fault activation „„„„„„„„„„„„„„„„„ 13 2.4 Summary of this chapter„„„„„„„„„„„„„„„„„„„„„ 17 3 Similarity Simulation on the Movement Law of overlying Strata in Normal Fault „„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„ 18 3.1 Design of equivalent material simulation experiment „„„„„„„„„„„ 18 3.2 Study on the movement law of overlying strata in normal fault „„„„„„„„23 3.3 Summary of this chapter„„„„„„„„„„„„„„„„„„„„„ 36 4 Analysis on Normal Fault Stress Evolution and Fault Activation Characteristics „„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„38 4.1 Introduction of simulation software FLAC3D „„„„„„„„„„„„„„38 4.2 Numerical model and simulation scheme „„„„„„„„„„„„„„„ 38 4.3 Evolution characteristics of mining stress when through normal fault mining„„„ 42 4.4 Study on normal fault activation law„„„„„„„„„„„„„„„„„ 50 4.5 Effects of different factors on mining stress and fault activation„„„„„„„ 57 4.6 Summary of this chapter „„„„„„„„„„„„„„„„„„„„„61 5 Engineering Example Verification „„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„ 63 万方数据 山东科技大学硕士学位论文 Contents IV 5.1 Theoretical basis of microseism„„„„„„„„„„„„„„„„„„„63 5.2 Micro seismic monitoring of working face in Dongtan coal mine 14310„„„„„66 5.3 Micro seismic monitoring of working face in Baodian coal mine 103down03„„„„70 5.4 Summary of this chapter„„„„„„„„„„„„„„„„„„„„„ 72 6 Main Conclusions„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„74 Main Reference Documents„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„76 Thanks„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„„ 81 Main Work Achievement of the Author during Working on Master Paper„„ 81 万方数据 山东科技大学硕士学位论文 绪论 1 1 绪论绪论 1.1 课题的提出及研究意义课题的提出及研究意义 我国是一个多煤少油少气的国家,目前已探明的煤炭储量占世里煤炭总储 量的 33.8,可采量位居世界第二,产量位居世界第一位[1]。煤炭在我国一次 性能源结构中一直处于绝对主要位置,随着大庆油田、渤海油田的发现和开发, 一次性能源结构才有了一定程度的改变,但煤仍然占到 70以上。 在中国 可持续能源发展战略研究报告中[2],20 多位院士一致认为,到 2050 年,煤 炭所占比例不会低于 50,可见煤炭能源在我国能源组成中占据极为重要的地 位,而且将是长期的和稳固的,具有不可替代性。 随着国民经济的快速发展,对煤炭资源的需求量日益上升,与此同时,我 国煤炭开采的地质水文条件也日益复杂,特别是在我国华东、华北、华中、西 南地区,大多数矿井地质条件复杂,很多矿井已由前期构造简单的采区转移至 现在构造复杂的采区。而在煤矿井下地质构造中,断层是最为常见的地质构造。 断层的存在打乱了岩层连续整体赋存的状态,在其附近应力分布异常,采动效 应十分突出,对开采设计、工作面布置、安全生产、开采技术及矿井产量等均 有重大影响,极易诱发冲击地压等动力灾害,造成严重的矿井灾害事故。 目前国内外学者对断层附近采动应力和断层活化规律进行了大量研究,但 主要是针对某工作面具体断层的特定条件或断层部分赋存状态,分析了断层附 近的应力分布规律,没有形成系统的、普遍的规律及定量预测方法,主要是解 决具体的工程问题,且以过断层开采为研究对象的较少。因此,本文根据正断 层的赋存状态与力学环境,通过相似材料模拟试验对正断层上、下盘工作面开 采过程中覆岩运移,尤其是断层活化期间两盘运动规律进行研究;通过 FLAC3D数值模拟,以双屈服模型模拟采空区,再现真实开采环境,系统地研 究上、下盘过正断层开采过程中工作面前方支承应力演化特征和断层活化规律, 解释断层带的采动应力阻隔效应及其机理,对指导现场煤炭资源开采和促进煤 矿安全高效生产具有重要意义。 1.2 国内外研究现国内外研究现状状 万方数据 山东科技大学硕士学位论文 绪论 2 1.2.1 断层附近采动应力研究现状断层附近采动应力研究现状 断层是影响煤层开采的重要地质因素,因断层切割了岩体的完整性,在煤 层回采过程中,致使断层附近应力异常,极易引发各种地质灾害。长期以来, 国内外学者和专家对断层附近采动应力进行了大量的深入研究。 史应恩[3]通过 FLAC3D数值软件研究了正、逆断层上盘向断层推进过程中 煤层底板岩层支承应力分布规律,研究认为断层活化前煤层底板岩层支承应力 峰值向靠近工作面煤壁方向转移,支承应力峰值不在增加。 郑朋强等[4]通过数值模拟研究了断层附近回采工作面采动应力分布规律, 结果表明断层存在不仅影响断层应力峰值,而且影响到支承应力分布形式和分 布范围,使应力峰值向煤壁转移,应力分布范围减小。 牛心刚等[5]研究了开采过程中断层对底板应力峰值与塑性区的影响,指出 底板应力峰值和破坏区范围随断层倾角的减小而增大,小倾角断层底板更容易 发生破坏。 高琳等[6]通过 FLAC 数值软件模拟了上、下盘向正断层推进过程中的工作 面前方支承应力演化规律,研究得出断层切割顶底板岩层完整性,阻隔效应显 著,致使断层煤柱内易形成应力集中,且正断层对上、下盘开采时支承应力阻 隔作用的大小不同。 王涛等[7]建立了沿上盘过断层回采的相似模型,研究了采动影响下断层应 力的演化特征,指出煤体内应力状态与断层滑移状态有关,工作面煤体应力在 断层滑移瞬间先降低后增加,呈现升高、降低交替往复形态。 何俊等[8]采用 ADINA 有限元数值软件模拟了煤层在断层构造应力场下破 坏情况及地应力的分布规律,模拟表明断层构造形成后,不同铅直应力和水平 应力组合条件下的正逆断层的下盘附近均存在应力集中现象。 徐传伟等[9]通过 UDEC 数值软件模拟了不同采高下盘工作面向逆断层推进 过程中支承应力的分布特征和演化规律。研究表明,受断层阻隔作用及煤柱效 应影响,断层煤柱内峰值呈现先小后大的变化趋势,明显影响范围不断减小, 采高较大时,煤层内的支承应力峰值较高,逆断层影响下的采动效应更为强烈。 吕进国等[10]以义马越近煤矿 25110 工作面断层诱发冲击灾害为案例,对逆 断层附近采动应力进行研究,指出 25110 工作面受逆断层影响而形成高强度支 承应力,断层带至下巷附近应力高度集中,为中级地压发生提供了力源条件。 万方数据 山东科技大学硕士学位论文 绪论 3 由此可见,断层切割了顶、底板的完整性,对采动应力存在一定的阻隔效 应,致使断层附近支承应力峰值及范围发生明显变异,采动效应十分显著,断 层煤柱内容易形成应力集中导致煤柱失稳,对工作面安全开采产生较大影响。 1.2.2 断层活化研究现状断层活化研究现状 断层活化是指岩体中的断层因受到采动影响而发生滑移的现象。工作面和 巷道附近的断层活化是造成冲击地压、冒顶、压架、突水等动力害的重要原因 之一,为此,国内外学者进行了有关研究工作,初步搞清楚了断层活化的变化 规律及主要影响因素。 于广明[11]等认为以往简单的把断层看为光滑面是不切实际的,其断裂面具 有各向异性特征,并通过数值模拟研究了断层几何形态对断层活化的影响,指 出采动断层活化分形效应显著,采场煤岩体的位移场和应力场随断层面维数的 变化而变化。 姜耀东等[12]通过库伦剪切模型的接触面单元代表断层上、下两盘接触状态, 数值模拟分析了从断层下盘或上盘向断层进对断层活化的影响,得出断层面上 法向应力受采动影响的敏感性早于剪切应力,且下盘开采对断层的影响范围更 为集中,活化危险更高。 吴基文等[13]针对任楼煤矿 F3F4 断层,模拟分析了回采过程中断层带的采 动影响及断层下盘的突水可能性,研究指出断层上、下盘随断层煤柱尺寸较小 变形规律不同,断层煤柱尺寸过小会使上、下盘岩体发生相对位移,导致断层 活化。 张培森等[14 17]分析了五沟煤矿 F16 断层的倾角,破碎带宽度及含水层水压 对断层应力场变化的影响。王涛等[18]针对义马千秋煤矿 21221 工作面附近 F16 逆断层,通过相似材料模拟实验研究了断层上盘滑移失稳规律,指出工作面煤 体承载力的局部失效极易引起断层滑移,断层面上的滑动位移分布具有非均匀 性,在积聚应变能的高应力区最早出现破坏和滑移。 Atsushi Sainoki 等[19]通过动态数值分析得出,断层受采动引起的最大剪切 位移与断层倾角、采深、断层与煤层的相对位置等因素有关,断层的刚度以及 剪胀角影响不大。 Md.Rafiqul Islam 等[20]通过数值模拟分析了孟加拉国 Barapukuri 煤矿主运输 巷道两条断层 Fb 和 Fb1 受采动活动规律。 万方数据 山东科技大学硕士学位论文 绪论 4 蒋