上覆采空区下坚硬顶板对煤体冲击的影响及其防治.pdf

国家重点研发计划（2016YFC0801403） 江苏省重点研发计划（BE2015040） 国家自然科学基金（51874292、51804303） 江苏省自然科学基金（BK20180643） 工程硕士专业学位论文 上覆采空区下坚硬顶板对煤体 冲击的影响及其防治 Influence of Hard Roof on Coal Burst and its Prevention in Overlying Goaf 作 者孙宇俊 导 师窦林名 教授 朱若军 高级工程师 中国矿业大学 二〇一九年五月 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 中图分类号 TD324 学校代码 10290 UDC 622 密 级 公开 中国矿业大学 硕士学位论文 上覆采空区下坚硬顶板对煤体 冲击的影响及其防治 Influence of Hard Roof on Coal Burst and its Prevention in Overlying Goaf 作 者 孙宇俊 导 师 窦林名 朱若军 申请学位工程硕士专业学位 培养单位 矿业工程学院 学科专业 矿业工程 研究方向 灾害防控 答辩委员会主席 徐金海 评 阅 人 盲审 二〇一九年五月 万方数据 致谢致谢 落笔于此，喜极而泣。适逢母校 110 年华诞，乃我辈之幸。回首矿大求学路，收获 满满，始终坚信当初报考并能够在矿大读研是我改变一生的正确决定。 首先感谢我的导师窦林名教授，老师优秀的做人品质、严谨的治学态度、谦逊的 处事风格以及忘我的工作精神都潜移默化地影响着我。从论文选题、内容构思到最后成 文，每一步都凝结着老师的智慧和心血。正是老师严格的要求、和蔼可亲的教导，使我 更加努力不敢松懈，能够跟随窦老师是我一生的荣幸。 感谢窑街煤电集团有限公司海石湾煤矿矿压办薛世智主任、马强技术员等在现场实 践中的指导、数据搜集方面的帮助和对科研项目的支持，在校外实践过程中和你们相处 十分愉快，深深感受到了煤矿人的豪爽和艰辛，至此，敬礼 论文的成功撰写离不开冲击矿压课题组老师、师兄弟的鼎立帮助，衷心感谢牟宗龙 教授、曹安业教授、巩思园副研究员、贺虎副教授、何江副教授、蔡武讲师、李许伟讲 师等在论文开题及预答辩中给予的指导，感谢王正义博士、王盛川博士、张敏博士、曹 晋荣博士、周坤友博士等在论文写作过程中给予的建议，特别感谢柴彦江博士、白金正 硕士、 陈为帅硕士、 李安宁硕士、王孟琦硕士、韩泽鹏硕士、 阚吉亮硕士、胡亚伟硕士、 杨扬硕士、孙振于工程师等同门师兄弟在数值模拟、资料收集和数据分析等方面提供的 帮助，能在冲击矿压课题组和这样一群优秀的人共事是我一生的财富。 感谢矿业工程学院、深部煤炭资源开采教育部重点实验室、采矿系的各位老师、领 导在科学研究上的支持与指导， 感谢他们为学生提供的优越的科研平台和良好的生活环 境。 感谢我辛勤的父母、兄长，正是他们默默无私的爱与支持，使我坚定地走在自己选 择的道路上。 采矿专业的艰苦与魅力感染了我， 毕业后将继续奋战在煤矿一线， “永远不服输， 永 远不向困难低头，永远争第一”的采矿精神时刻铭记我心。作为一名身在“最底层”的 挖煤人，将继续为祖国的能源建设贡献自己绵薄之力，为人民继续带来光明和温暖 最后，向百忙之中审阅本文和参加论文答辩的各位老师、专家致谢，由于本文水平 有限，文章中难免有谬误之处，恳请专家、教授批评指正，不甚感激 孙宇俊 农历己亥孟夏廿四于徐 万方数据 I 摘摘 要要 冲击矿压作为一种典型的煤矿动力灾害，随着煤矿开采深度和强度的加大，其冲击 显现愈加频发，而开采上覆煤岩层（保护层）是有效防治冲击矿压的区域性措施之一， 但保护层开采后，被保护的煤层回采时也存在冲击矿压危险。窑街海石湾煤矿在上覆油 页岩保护层已回采结束的情况下，煤二层 6124-1工作面回采时，回风顺槽仍出现底鼓、 帮鼓、锚杆锚索失效等冲击显现。因此本文以窑街海石湾矿 6124-1工作面为研究背景， 对油页岩已采情况下，煤二层开采过程中发生的冲击规律进行研究，论文主要取得进展 如下 油页岩的开采提前形成较大范围的覆岩运动，在其采后一定时间内上覆岩层以“砌 体梁”的结构形式存在，在煤二层开采后，将使原先形成的已稳定结构二次活化，导致 煤二层开采后覆岩运动更加剧烈。 而在油页岩与煤二层之间存在坚硬厚层砂岩顶板的不 利因素之下时，由于坚硬顶板较难破断，在煤二层采后临空侧可能形成“悬臂梁悬臂 梁” 、 “悬臂梁砌体梁” 、 “砌体梁砌体梁”和“砌体梁悬臂梁”四种结构。最后依据 关键层判别和岩层破断时的临界开采长度理论， 发现油页岩的开采导致的覆岩发育高度 较无油页岩开采时更高。 通过数值模拟分析表明①油页岩的开采可以有效降低静载应力水平，说明上覆岩 层开采具有区域卸压效果； ②上覆岩层的卸压效果与保护距离关系密切， 保护距离越大， 卸压程度越差； ③上覆岩层的卸压效果与油页岩和煤二层之间存在的岩层岩性关系较大， 随岩层岩性强度变大，卸压效果衰减；④通过采用不同动载荷模拟坚硬顶板破断，在动 载荷60MPa 时，对顺槽影响明显突变，在动载 荷为 100MPa 时，对顺槽破坏性最强。 针对油页岩与煤二层之间存在坚硬顶板的特殊情况， 提出了上覆岩层开采下坚硬顶 板对煤体冲击的机理，认为油页岩的开采可以有效降低煤二层静载应力水平，并且建立 了油页岩采后的应力分布表达式；而坚硬顶板的存在，其临空侧形成的悬顶将承受更大 的载荷，经力学推导，得出悬顶积聚的弹性能是载荷集度的二次抛物函数，最终二者叠 加形成“高动载-低静载”型的冲击模式。 根据研究成果，设计了窑街海石湾矿 6124-1工作面具有针对性的监测预警和防治体 系，主要进行了工作面采前预评价与开采过程中预警和防治，通过再次削弱静载荷与切 断动载荷载体二者同步进行，有效地对冲击矿压危险程度进行了监测和防治，在现场取 得很好应用。 该论文有图 67 幅，表 17 个，参考文献 96 篇。 关键词关键词冲击矿压；上覆采空区；坚硬顶板；防治技术 万方数据 II Abstract Rock-burst as a kind of typical coal mine dynamic disaster, as the increase of mining depth and intensity, its rockburst appeared more and more frequent, and the mining overlying rock strata protection strata is one of the effective prevention and control of rock-burst regional measures, but after the protective strata mining, the protected coal seam also has the risk of rock burst in the mining process. Under the circumstance that the overlying oil shale protective strata of HaiShiwan coal mine has finished in YaoJie, the 6124-1 working face still shows the rockburst of floor heave, side heave and failure of anchor bolt and anchor cable.Therefore, this paper takes the 6124-1 working face of HaiShiwan coal mine inYaoJie, as the research background to study the rockburst law occurring in the No. 2 coal seam mining process under the condition that oil shale has been extracted. The main progress of this paper is as follows The overburden strata exist in the of “masonry beam“ within a certain period of time after mining. After mining on the No. 2 coal seam, the previously ed stable structure will be reactivated, resulting in more violent overburden movement after mining on the No. 2 coal seam.However, under the adverse factors of hard and thick sandstone roof between oil shale and No. 2 coal seam, since the hard roof is difficult to break, there may be four types of structures “cantilever beam cantilever beam“, “cantilever beam masonry beam“, “masonry beam masonry beam“ and “masonry beam cantilever beam“ in the hollow side of No. 2 coal seam after mining.Finally, according to the key strata discrimination and the critical mining length theory, it is found that the development height of overburden caused by oil shale mining is higher than that without oil shale mining. The numerical simulation analysis shows that ①the exploitation of oil shale can effectively reduce the level of static stress, indicating that the overburden mining has regional pressure relief effect;②the overburden pressure relief effect is closely related to the protection distance, the greater the protection distance, the worse the pressure relief degree;③the pressure relief effect of overlying strata has a great relationship with the lithology of rock strata existing between the oil shale and No. 2 coal seam, as the lithology strength of rock strata increases, the pressure relief effect attenuates.④ through the use of different dynamic load simulation of hard roof break, in the dynamic load 60MPa, the impact on the roadway obvious mutation, in the dynamic load is 100MPa, the most destructive to the roadway. In view of the special situation that there is a hard roof between the oil shale and the No. 2 coal seam, this paper puts forward the rockburst mechanism of the hard roof under the 万方数据 III overburden mining on the coal, and thinks that the oil shale mining can effectively reduce the level of the static load stress on the No. 2 coal seam and establishes the stress distribution expression after the oil shale mining.In the presence of hard roof, the suspended roof ed on its gob-side roadway will bear more load. Through mechanical derivation, it is concluded that the elastic energy accumulated on the suspended roof is the quadratic parabolic function of load intensity, and finally the superposition of the two s the rockburst mode of “high dynamic load - low static load“. According to the research results, the design of 6124-1 face of HaiShiwan coal mine inYaoJie targeted monitoring and early warning and control system, main pre-assessment before working face mining and mining process monitoring, prevention and by weakening the static load again and cutting off the dynamic load carrier, to effectively predict and control the rockburst risk and good application in the field. This thesis has 67 figures, 17 tables and 96 references. Keywords rock burst；overlying goaf; hard roof；control technology 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 变量注释变量注释表表 ........................................................................................................................... XIII 1 绪论绪论 ......................................................................................................................................... 1 1.1 研究背景及意义 .............................................................................................................. 1 1.2 研究现状概况 .................................................................................................................. 1 1.3 主要研究内容 .................................................................................................................. 4 1.4 技术路线 .......................................................................................................................... 5 2 上覆采上覆采空区下采场覆岩空间结构演化规律研究空区下采场覆岩空间结构演化规律研究 ................................................................. 6 2.1 煤层上覆岩层破断特征 .................................................................................................. 6 2.2 煤层上覆岩层破断演化规律 ........................................................................................ 11 2.3 小结 ................................................................................................................................ 19 3 上覆采空区下采动效应的数值模拟研究上覆采空区下采动效应的数值模拟研究 ........................................................................... 21 3.1 数值模型和模拟方案设计 ............................................................................................ 21 3.2 静载应力场分布规律 .................................................................................................... 23 3.3 动载应力场作用效应 .................................................................................................... 38 3.4 小结 ................................................................................................................................ 44 4 上覆采空区下坚硬顶板诱发煤体冲击上覆采空区下坚硬顶板诱发煤体冲击模式分析模式分析 ............................................................... 46 4.1 上覆采空区下静载应力降低分布规律 ........................................................................ 46 4.2 上覆采空区下动载应力强化分布特征 ........................................................................ 52 4.3 上覆采空区下动静载叠加诱冲模式 ............................................................................ 56 4.4 小结 ................................................................................................................................ 57 5 上覆采空区下防冲技术应用研究上覆采空区下防冲技术应用研究 ....................................................................................... 58 5.1 工作面冲击危险采前预评价 ........................................................................................ 58 5.2 工作面冲击危险监测预警 ............................................................................................ 59 万方数据 V 5.3 工作面冲击危险防治措施 ............................................................................................ 67 5.4 工作面冲击危险防治效果检验 .................................................................................... 72 5.5 小结 ................................................................................................................................ 76 6 主要结论主要结论 ............................................................................................................................... 77 参考文献参考文献 .................................................................................................................................. 79 作者简历作者简历 .................................................................................................................................. 85 学位论文原创性声明学位论文原创性声明 .............................................................................................................. 86 学位论文数据集学位论文数据集 ...................................................................................................................... 87 万方数据 VI Contents Abstract .................................................................................................................................... II Contents ................................................................................................................................... VI List of Figures ...................................................................................................................... VIII List of Tables ......................................................................................................................... XII List of Variables ................................................................................................................... XIII 1 Introduction ........................................................................................................................... 1 1.1 Research Significance and Background of Thesis ........................................................... 1 1.2 Research Status ................................................................................................................ 1 1.3 Main Research Objectives ................................................................................................ 4 1.4 Technical Route ................................................................................................................ 5 2 Study on Evolution of Overlying Strata Spatial Structure in Overlying Goaf ................ 6 2.1 Fracture Characteristics of Overlying Strata of Coal Seam ............................................. 6 2.2 Fracture Evolution of Overlying Strata in Coal Seam ................................................... 11 2.3 Summary ........................................................................................................................ 19 3 Numerical Simulation on Mining Effect in Overlying Goaf ........................................... 21 3.1 Design of Numerical Model and Simulation Scheme .................................................... 21 3.2 Distribution Law of Static Stress Field .......................................................................... 23 3.3 Effect of Dynamic Stress Field ...................................................................................... 38 3.4 Summary ........................................................................................................................ 44 4 Analysis on Coal Samples Rockburst Mode Induced by Hard Roof in Overlying Goaf .............................................................................................................................................. 46 4.1 Analysis of Static Load Reduction in Overlying Goaf ................................................... 46 4.2 Analysis of Dynamic Load Rise in Overlying Goaf ...................................................... 52 4.3 Analysis of Rockburst Induced by Superposition of Dynamic and Static Loads in Overlying Goaf ............................................................................................................. 56 4.4 Summary ........................................................................................................................ 57 5 Research on Application of Preventing Rockburst in Overlying Goaf .......................... 58 5.1 Pre-assessment of Working Face Rockburst Risk .......................................................... 58 万方数据