软岩巷道围岩破坏特征及注浆支护研究.pdf

万方数据 国家自然科学基金（国家自然科学基金（NO.51474136）） 国家自然科学国家自然科学基金基金青年基金（青年基金（NO.51704181）） 论文题目论文题目 软岩巷道围岩破坏软岩巷道围岩破坏特征特征及注浆及注浆支护支护研究研究 作者姓名作者姓名 李李 刚刚 入学时间入学时间 2015 年年 9 月月 专业名称专业名称 工程力学工程力学 研究方向研究方向 矿矿 山山 岩岩 石石 力力 学学 指导教师指导教师 谭云亮谭云亮 职职 称称 教教 授授 赵同彬赵同彬 教教 授授 论文提交日期论文提交日期 2018 年年 5 月月 论文答辩日期论文答辩日期 2018 年年 5 月月 授予学位日期授予学位日期 2018 年年 6 月月 万方数据 FAILURE CHARACTERISTICS AND GROUTING SUPPORT OF SURROUNDING ROCK IN SOFT ROCK ROADWAY A dissertation ted in fulfillment of the requirements of the degree of MASTER OF ENGINEERING from Shandong University of Science and Technology by Li Gang Supervisor Professor Tan Yunliang College of Mining and Safety Engineering MAY 2018 万方数据 万方数据 万方数据 万方数据 山东科技大学硕士学位论文 摘要 I 摘要摘要 我国西部煤矿开采过程中经常遇到强度低、胶结差、遇水泥化的软岩，导致 锚固支护方式不能长期有效维持巷道稳定，巷道变形破坏严重。开展软岩巷道围 岩变形破裂机理及注浆支护研究具有重要的理论意义和工程实用价值。 本文以鄂 尔多斯红庆梁煤矿为工程背景，采用理论分析、数值模拟、室内试验及现场工程 相结合的方法，进行系统地研究，主要工作如下 首先，对巷道顶板煤、砂质泥岩进行物理力学特性测试，得到煤的强度大于 砂质泥岩，后者软岩特征明显，平均单轴抗压强度小于 20MPa，并分析加载过 程中砂质泥岩层理对其强度及变形破坏影响规律； 进行砂质泥岩物性成分分析及 水理试验，研究了水对砂质泥岩强度的弱化效应，总结其破裂特征。 其次，探测了巷道变形破坏特征，顶板岩层层理、裂隙发育破坏范围大，顶 板破裂、下沉剧烈、破裂严重，煤壁极易发生片帮、内挤显著，顶板锚杆（索） 锚固力不足，巷帮支护结构损坏严重。借助 FLAC 数值模拟软件，对巷道开挖宽 度、 水平应力大小及岩层层理对巷道稳定性的影响进行分析，随着巷道宽度的增 加，顶板岩层塑性区向两侧及深部扩展；随着水平应力的增大，巷帮围岩塑性区 减小，并向巷道顶底板转移；砂质泥岩层理对其强度及变形破坏有较大影响，通 过数值模拟降低层理间粘结强度， 顶板岩层塑性区在水平和竖直方向均显著增加。 最后，根据巷道围岩破坏机理提出注浆加固方案，室内试验结果表明，水泥 浆、水玻璃-水泥浆液基本性能受水灰比、体积比等配比方式的影响很大，浆液 固结体内聚力、内摩擦角等强度参数较砂质泥岩有 20-30的提高，浆液固结 体破坏以结石体与岩块交界面及浆液结石体骨架破坏为主。数值模拟结果表明， 对巷道顶板岩层进行注浆加固， 顶板注浆岩层区域宽度应大于巷道宽度的1.4倍； 水平应力较小情况下，通过增加注浆岩层宽度可提高巷道围岩控制效果；较高水 平应力情况下，注浆区域高度提升至 6m、提高强度可取得良好控制效果。通过 注浆有效提高了锚固支护性能，巷道顶底板移近量较未注浆区段减少超过 50， 支护效果良好。 关键词关键词软岩巷道；围岩破裂特征；注浆试验；FLAC 数值模拟 万方数据 山东科技大学硕士学位论文 Abstract II ABSTRACT In the process of coal mining in western China, soft rock characterized by low strength, poor cementing, and degradation and softening in water is often encountered, which results in the failure of anchorage support s to maintain roadway stability for a long period of time, and roadway deation and destruction. It is of great theoretical significance and engineering practical value to carry out research on deation, failing mechanism of surrounding rock in soft rock roadway and grouting support. This article takes the Hongqingliang Coal Mine as the engineering background, and uses a combination of theoretical analysis, numerical simulation, indoor test and field test to conduct systematic research. The main work is as follows Firstly, the mechanical properties of the roadway roof coal and rock were tested. The strength of the coal was greater than that of the sandy mudstone. Sandy mudstone belongs to soft rock and has an average uniaxial compressive strength under 20 MPa and analyzes the influence law of sandstone bedding on its strength and deation during loading, and analyzes the physical components and water physical characteristics of sandy mudstone. the effect of water on the strength of sandy mudstone was analyzed and the fracture characteristics were revealed. Secondly, the characteristics of roadway deation and failure are explored, the roof rock bedding, crack development and damage scope, roof cracking, drastic droop, and frequent roof fall accidents; coal wall is prone to rib spalling and internal extrusion; The anchor bolts cables of the roadway roof are insufficient for anchorage, and the roadway support structure is seriously damaged.Combining engineering geological conditions and FLAC numerical simulation software to analyze the influence of tunnel excavation width, horizontal stress magnitude, and strata bedding on roadway stability. analysis shows that as the width of the roadway increases, the stress concentration point moves to the deep rock mass, the range of plastic zone in the rock strata expands; as the horizontal stress increases, the plastic zone of the rock mass decreases, and transfer to the roof and floor of the tunnel; the shear strength between bedding decreases, which leads to a significant increase in the plastic zone of strata in both the horizontal and 万方数据 山东科技大学硕士学位论文 Abstract III vertical directions. Finally, the grouting reinforcement governing project was proposed according to the failure mechanism of surrounding rock. The results of grouting reinforcement test showed that the basic perance of cement slurry, water glass-cement slurry was greatly influenced by the ratio of water to cement, volume ratio, etc. The cohesive strength, internal friction angle and other strength parameters are all higher than those of sandy mudstone. The damage of consolidation body is mainly based on the interface between stone body and rock mass and the destruction of grout stone structure. The results of numerical simulation show that the grouting reinforcement of the roof rock strata in the roadway, the width of the grouting layer of the roof should not be less than 1.4 times the width of the roadway; under the condition of small horizontal stress, the effect of the control of the roadway surrounding rock can be improved by increasing the width of the grouting rock. In the case of high-level stress, it is necessary to increase the height to 6m and improve strength of the grouting area to achieve the control effect. Through grouting, the anchorage supporting perance is effectively improved, and the roadway roof and floor movement is reduced by more than 50 compared with the non-grouting section. The supporting effect is good. Keywords Soft rock roadway; Failure characteristics; Laboratory grouting test; FLAC numerical simulation 万方数据 山东科技大学硕士学位论文 目录 IV 目录目录 1 绪论绪论 ......................................................................................................... 1 1.1 课题的提出及研究意义......................................................................................... 1 1.2 国内外研究现状..................................................................................................... 1 1.3 主要研究内容与技术路线..................................................................................... 5 2 软岩巷道围岩破裂特征研究软岩巷道围岩破裂特征研究 ................................................................ 7 2.1 矿井工程地质概况................................................................................................. 7 2.2 软岩巷道围岩物理力学特征................................................................................. 8 2.3 软岩巷道围岩变形破裂特征............................................................................... 14 2.4 本章小结............................................................................................................... 17 3 软岩巷道围岩破裂影响因素分析软岩巷道围岩破裂影响因素分析 ...................................................... 18 3.1 矩形巷道围岩应力............................................................................................... 18 3.2 巷道宽度对围岩破裂的影响............................................................................... 21 3.3 侧压力系数对围岩破裂的影响........................................................................... 25 3.4 顶板岩层强度弱化对顶板破裂的影响............................................................... 28 3.5 本章小结............................................................................................................... 35 4 软岩巷道顶板围岩注浆室内试验研究软岩巷道顶板围岩注浆室内试验研究 .............................................. 37 4.1 水泥注浆材料性能试验研究............................................................................... 37 4.2 水玻璃-水泥配比试验研究 ................................................................................. 42 4.3 注浆加固效应试验............................................................................................... 44 4.4 本章小结............................................................................................................... 48 5 软岩巷道顶板注浆支护参数设计软岩巷道顶板注浆支护参数设计 ...................................................... 49 5.1 注浆加固机理....................................................................................................... 49 5.2 锚注支护参数优化设计....................................................................................... 51 5.3 现场注浆方案....................................................................................................... 56 5.4 现场试验效果分析............................................................................................... 58 万方数据 山东科技大学硕士学位论文 目录 V 5.5 本章小结............................................................................................................... 61 6 结论与展望结论与展望 .......................................................................................... 62 6.1 主要结论............................................................................................................... 62 6.2 创新点................................................................................................................... 63 6.3 不足与展望........................................................................................................... 63 参考文献参考文献 .................................................................................................. 64 致谢致谢 ........................................................................................................... 71 攻读硕士期间主要成果攻读硕士期间主要成果 .......................................................................... 71 万方数据 山东科技大学硕士学位论文 Content VI Contents 1 Introduction..............................................................................................................1 1.1 Research Background and Significance....................................................................................1 1.2 Research Status at Home and Abroad..................................................................................1 1.3 Main Research Contents and Technical Routes...................................................................5 2 Deation and failure feature of wall rock in soft rock roadway..........7 2.1 Mining Engineering Geological Survey.................................................................................7 2.2 Physical and mechanical properties of surrounding rock in soft rock roadway..............8 2.3 Deation and Fracture feature of wall Rocks of Soft Rock Roadway ...................14 2.4 Brif Summary..........................................................................................................................17 3 Analysis of influence factors on fracture of soft rock roadway surrounding rock..............18 3.1 Surrounding rock stress in rectangular roadway................................................................18 3.2 Influence of Different Tunnel Width on Deation and Failure of wall Rock.........21 3.3 Influence of Side Pressure Coefficient on Deation and Failure of Surrounding Rock....25 3.4 Analysis of Deation and failure of Composite Laminated Roof..............................28 3.5 Brif Summary..........................................................................................................................35 4 Experimental study on grouting of wall rock in soft rock roadway........37 4.1 Experimental study on perance of cement grouting material....................................37 4.2 Water Glass-Cement Proportioning Test...............................................................................42 4.3 Grouting reinforcement effect test........................................................................................44 4.4 Brif Summary..........................................................................................................................48 5 Design of roof grouting support parameters for soft rock roadway.........49 5.1 Grouting reinforcement mechanism...49 5.2 Site grouting scheme......................................................................................51 5.3 Anchorage support parameter optimal design.....................................................................56 5.4 Field application effect analysis............................................................................................68 5.5 Brif Summary..........................................................................................................................61 6 Conclusion and Prospects....................................................................................62 6.1 Main Conclusion.....................................................................................................................62 6.2 Innovation Points.63 6.3 Insufficiency and outlook.......................................................................................................63 Reference.....................................................................................................................64 Acknowledgement......................................................................................................71 Main Achievements and Rewardings During the Master.......................................72 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 我国是消费大国，煤炭在我国一次能源消费中占有很大比重；其分布极不均 衡，总体分布的特征为“西多东少、北丰南贫、相对集中”[1-3]。随着我国中东 部浅部煤炭资源趋于枯竭，矿井开采逐渐向并向新疆、内蒙古等煤炭资源丰富西 部矿区发展[4-6]，伴随着我国西部大开发战略等战略的提出，加快了对西部地区 煤炭等资源的开发和利用。 由于我国西部弱胶结软岩成岩时间一般较短，粘土矿物含量高，造成了其强 度低、胶结差、易风化、遇水泥化等特点导致巷道难以有效维持长期稳定[7-11]。 在弱胶结软岩中开掘的巷道，由于岩层中蒙脱石、高岭石及伊利石等粘土矿物遇 水容易泥化，岩石力学性质降低且不均匀，造成巷道围岩自承载能力极低、自稳 能力差、自稳时间短极易产生巷道大变形，且变形持续时间较长，易出现底鼓、 片帮、 冒顶等工程灾害问题[12-14]； 岩体组成为泥质胶结， 其胶结性极弱或未胶结， 导致岩体的内摩擦角和内聚力较低，造成锚固力低，极易脱锚[15,16]。 论文以红庆梁煤矿首采面辅运顺槽支护工程为研究背景， 对软岩巷道围岩变 形破裂机理及注浆支护进行研究。红庆梁煤矿具有典型的西部弱胶结软岩地层， 位于东胜煤田北部边缘，处于华北板块、蒙古板块及松辽板块三大板块的相接地 段[17-19]，复杂的地质构造使巷道支护更加困难。 红庆梁煤矿煤层顶底板围岩以弱胶结砂质泥岩为主，裂隙及层理发育，围岩 遇水软化，巷道围岩自承载能力极低、自稳能力差。11301 首采面顺槽支护完成 使用一段时间后，出现顶板开裂、冒顶、底鼓以及锚杆、锚索锚固失效等问题， 造成巷道变形破坏严重，不能长期有效维持巷道稳定，而且其破坏形式与软岩巷 道常见围岩分区破坏特征不同。采用理论分析、数值模拟、室内试验及现场试验 相结合的方法，对软岩巷道围岩破裂机理及注浆支护进行研究，为巷道科学支护 提供依据。 1.2 国内外研究现状国内外研究现状 1.2.1 软岩巷道支护理论国内外研究现状软岩巷道支护理论国内外研究现状 软岩工程支护关键是确定支护载荷， 因此支护理论发展与围岩压力理论发展 万方数据 山东科技大学硕士学位论文 绪论 2 密切关联，支护理论发展可以划分三个阶段[20-24]古典压力理论、散体压力理论 及弹塑性变形压力理论。古典压力理论认为上覆岩层自重是支护结构压力来源， 该理论仅适用于工程埋深较小的情况。 散体压力理论认为支护体结构压力来自围 岩冒落拱内岩石自重，但散体压力理论未考虑围岩的变形因素，只适应于的浅部 疏松岩层。岩石力学认为围岩即是支护载荷，同时是承载结构，支护的作用是阻 止围岩变形； 塑性区适量扩展使围岩承载能力得以发挥， 支护体与围岩共同承载， 减小支护结构受力。这为巷道支护设计提供了重要理论依据，对大变形软岩巷道 支护有重要指导意义。常见国外软岩巷道支护理论见表 1.1。 表 1.1 国外主要软岩巷道支护理论[20,21] Table1 The main soft rock roadway support theory abroad 发展 阶段 提出 时间 理论 主要观点 代表人物 第一 阶段 20 世纪 20 年代 古典压力 理论 上覆岩层是支护结构压力来源； 由于未曾考虑 围岩自承载能力，只适于浅埋深地下工程。 海姆、郎金 第二 阶段 20 世纪 50、60 年 代 散体压力 理论 地下工程埋深较大， 作用在支护结构上的压力 是围岩塌落拱内岩体重力， 塌落拱的高度与地 下工程的跨度及围岩的性质相关。 太沙基、普罗 托季亚科诺夫 第三 阶段 20 世纪 60 年代 新奥法 发挥围岩的自承作用来， 促使围岩成为支护结 构组成部分，共同形成为支撑结构。 奥地利 L.V.拉 布釆维茨 20 世纪 60 年代 应变控制 理论 使用支护体将围岩变形限制在允许