清水营煤矿软岩巷道锚注支护技术研究.pdf

论文题目清水营煤矿软岩巷道锚注支护技术研究 专 业矿业工程 硕 士 生叶 平 （签名） 指导老师伍永平 （签名） 肖 蕾 （签名） 摘 要 自上世纪八十年代以来，新奥法支护在我国煤矿巷道中得到了全面推广应用，并经 过近 30 年的发展形成了以锚杆为主体的各种支护结构，如煤巷锚网支护、锚带网索支 护；岩巷锚喷支护、锚网喷支护、锚网喷索支护等，对保证巷道的有效使用发挥了重要 作用。但是，新奥法支护在软岩巷道却遇到了很大的困难，除软岩自身的因素外，锚杆 索在软岩内锚固点不易形成是关键因素之一，影响了锚杆索的支护强度，造成软岩巷道 围岩变形得不到有效控制， 导致巷道支护失效而发生破坏。 本文综合运用工程地质调查、 实验室力学性质测试与物相分析、 现场地应力实测、 理论分析和现场观测等方法和手段， 分析了清水营煤矿软岩巷道围岩失稳破坏特征、软岩锚注前后特性，提出了锚网喷索 锚注联合支护技术，并获得良好的技术经济效益。获得了如下研究成果 （1）清水营煤矿786m 水平井底车场具有明显的软岩特征其所在层位的岩性为 粉砂岩，厚度为 14.8m，试验其抗压强度仅为 1.59MPa；化验其膨胀性矿物成份含量分 别为伊利石含 29.3，绿泥石含 30.7；实测的最大水平应力为 23.74MPa，竖向自重 应力为 16.37MPa，两者比值为最大水平应力是竖向自重应力的 1.45 倍。 （2）以清水营煤矿786m 水平井底车场为工程背景进行锚注支护数值分析，结果 表明巷道开挖至未支护时，围岩变形破坏严重，采用锚注支护后，锚杆起到一定作用， 但随着时间推移仍发生了较大的变形破坏，进行锚注加强支护后，在巷道周围形成了一 个厚壁承载拱，在同样的竖向压力作用下，巷道变形较小，证明锚注支护够对巷道围岩 进行有效控制。并将软岩按水灰比 0.8 的水泥浆与粉砂岩颗粒制作力学模型，进行锚注 特性试验得出；锚注前试件的抗压强度峰值为 11.585MPa，锚注后试件的抗压强度可达 22.22MPa，可见软岩锚注后其自承能力比锚注前提高了 1.92 倍。 （3）通过对清水营煤矿786m 水平井底车场的变形原因进行分析，根据车场巷道 的软岩性状、物相成份及地应力特点，针对性了提出了锚网喷索锚注联合支护设计方 案，并在车场巷道中进行工程实践，实践证明锚注后明显改善了围岩的力学性质，提 高了围岩了自承能力， 巷道围岩得到了较好的控制。 通过近 100 天的监测结果可以看出 巷道拱部下沉量 21mm，帮部移近量 25mm，且喷层未出现任何开裂现象；锚注后声波测 试速度比注浆前提高了 16～45，弹性模量提高了 34～110；经过钻孔窥视，注 浆后孔内光滑密实，表明浆液有效的充填了围岩内的松动裂隙，使松动破坏的围岩重新 胶结在了一起，提高了其密实性和完整性，这对软岩的有效控制和长期稳定起到了重要 作用。 本文的研究成果经在786m 水平井底车场应用试验后达到了预期目的。 证明软岩巷 道采用“锚网喷索锚注”支护是一种有效的方法之一，目前该方法已在786m 水平井 底车场所有软岩巷道和硐室中得到了全面推广应用， 同时对其它矿井的软岩巷道支护也 具有良好的借鉴意义。 关 键 词软岩；锚注；巷道支护。 研究类型应用研究 Subject Research on the Bolt-grouting Supporting Technology of Soft Rock Roadway in Qing Shuiying Coal Mine Specialty Mining Engineering Name Ye Ping （（Signature）） Instructor Wu Yongping （（Signature）） Xiao Lei （（Signature）） Abstract Since 1980s, NATM has got a comprehensive application in our country’s coal mines’ field, and after nearly 30 years of development, has ed anchor and other similar supporting structures such as anchor nets supporting and cable anchor supporting used in coal roadway. Using spray the anchor, anchor net and anchor cable supporting technique. This kind of support plays an important role in ensuring the effective control of the coal roadway. However, new Austrian was confronted with great difficulties in the supporting of the weak rock roadway. Apart from the nature of the weak rock, the anchor cable has no root point in the weak rock, thus affects the strength of the anchor cable support and the effective control of the weak rock coal tunnel. Through integrated s of engineering geological, theoretical analysis, physical simulation, numerical simulation, site test and so on, the evolution and characteristics of deation and failure of surrounding rock roadway of Qing Shuiying Colliery are studied, and the anchor net spray supportbolt-grouting supporting technology is proposed. The research productions have been applied successfully in project of support in underground engineering, and the chief conclusions achieved are shown as follows （1）The lithology of 786m level bottom seat strata is siltstone, its thickness is 14.8m, the tested compressive strength is only 1.59MPa; laboratory tests for its expansive minerals content are respectively illite containing 29.3, chlorite 30.7; the measured maximum horizontal stress is in 23.74MPa, vertical stress for 16.37MPa, both ratio of maximum horizontal stress and vertical stress is 1.45 times. （2）With the anchor note supporting numerical analysis for the 786m level bottom heavy vehicle line,the results show that surrounding rock mass deation damage is serious when the roadway excavation to not support ,and anchor play a role if the anchor note support was used,but with time still changered a lot of deation and destruction,the anchor note strengthen support,in tunnels developed around a thick wall bearing arch,in the same vertical pressure effect,small roadway deation prove anchor supportingof roadway surrounding rock is the effective contol. In order to obtain the pre and post test results of the soft rock and siltstone bolting and grouting, the soft rock particle production mechanics model according to water cement ratio of 0.8 mud and water was established.Theanchor note characteristic test show that namely the peak strength bofore being bolted and grouted is 11.585Mpa and after is 22.22MPa. We can see the bearing capacity of soft rock increased by 1.92 times after bolted and grouted than bofore. （3） According to the mechanical test and theoretical analysis results, the supporting test on the 786m level bottom heavy vehicle line with the test scheme which is “ anchor net rope and anchor,“ then choose the reasonable support parameters and after carrying out getting the result one is the 100d convergence deation monitoring, its arch sinkage is 21mm, sidewall sinkage is 25mm, and the spray layer without any cracks and rock pressure phenomena, indicating heavy vehicle line rock has been effectively controled；two is a soft rock acoustic velocity ratio increased by 1645 after grouting, dynamic elastic modulus increased by 34110, shows that after grouting soft rock’s physical and mechanical properties have been effectively improved; three is observed before drilling peep, grouting hole rock loose and broken, and the emergence of serious hole collapse phenomenon, and the grouting hole rock smooth and compact, effective grout filling the surrounding rock loosening fissures, increases its compactness and completeness of the soft rock, this has played an important role in effective control and long-term stability. Therefore, the results of this study have been tested in the 786m level bottom heavy vehicle line and the test has achieved the expected objective. Proved that soft rock tunnel using “anchor net spray supportbolt-grouting support ”is one of the most effective s, now the has been widely used in all soft rock roadway and chamber of the 786m level bottom, meanwhile it also provides a good reference for other mine’s soft rock roadway support. Key words Soft rock Bolt-grouting Roadway supporting Research type Application resaerch 目录 I 目 录 目 录 1 绪论........................................................................................................................................1 1.1 问题的提出 .....................................................................................................................1 1.2 研究意义 ..........................................................................................................................1 1.3 软岩巷道支护理论国内外研究现状 .............................................................................1 1.3.1 国外软岩巷道支护理论研究现状...........................................................................1 1.3.2 国内软岩巷道支护理论研究现状...........................................................................2 1.4 软岩巷道支护技术国内外研究现状 .............................................................................5 1.4.1 国外软岩巷道支护技术研究现状...........................................................................5 1.4.2 国内软岩巷道支护技术研究现状...........................................................................7 1.4.3 软岩锚注支护技术的发展.......................................................................................9 1.5 软岩支护存在的问题 ...................................................................................................10 1.6 课题研究内容、研究方法及技术路线 .......................................................................11 1.6.1 研究内容.................................................................................................................11 1.6.2 研究方法及技术路线.............................................................................................11 2 清水营煤矿软岩巷道围岩变形破坏特征与机理分析......................................................13 2.1 软岩巷道的界定 ............................................................................................................13 2.2 围岩变形破坏机理....................................................................................................13 2.2.1 物理力学试验.........................................................................................................13 2.2.2 地应力测量.............................................................................................................15 2.2.3 物相成份化验.........................................................................................................18 2.3 巷道变形破坏特征 .......................................................................................................18 2.3.1 巷道开挖瞬间的围岩弹性变形..............................................................................18 2.3.2 巷道支护前的围岩变形.........................................................................................18 2.3.3 巷道支护后的围岩变形.........................................................................................19 2.3.4 巷道支护失稳的围岩变形.....................................................................................19 2.4 本章小结....................................................................................................................20 3 清水营煤矿巷道软岩锚注特性试验..................................................................................21 3.1 软岩锚注特性试验 ........................................................................................................21 3.1.1 试样制作.................................................................................................................21 3.1.2 试验内容.................................................................................................................21 3.1.3 测试系统.................................................................................................................21 3.2 软岩锚注特性分析 .......................................................................................................22 3.2.1 单轴压缩试验单向应力状态.............................................................................22 3.2.2 侧向约束试验两向应力状态.............................................................................23 目录 II 3.3 软岩锚注机理研究 ........................................................................................................24 3.3.1 锚注加固的概念......................................................................................................24 3.3.2 锚注加固的承载机理.............................................................................................24 3.3.3 锚注组合拱参数.....................................................................................................25 3.3.4 锚注参数分析..........................................................................................................26 3.4 软岩锚注极限承载能力............................................................................................28 3.5 本章小结.....................................................................................................................30 4 清水营煤矿软岩锚注支护方案数值模拟研究..................................................................31 4.1 RFPA 程序及特点..........................................................................................................31 4.2 模拟分析........................................................................................................................31 4.3 本章小结 .......................................................................................................................38 5 工程应用..............................................................................................................................39 5.1 工程概况 .......................................................................................................................39 5.1.1 矿井地质情况 ............................................................................................................39 5.1.2 786m 水平井底车场变形破坏状况及原因分析..................................................39 5.2 锚注支护方案设计 ........................................................................................................40 5.2.1 各支护结构的比较 ....................................................................................................40 5.2.2 支护方案确定 ............................................................................................................41 5.3 锚注支护基本参数确定 ................................................................................................42 5.3.1 锚杆支护参数.........................................................................................................42 5.3.2 锚索支护参数分析.................................................................................................43 5.3.3 注浆参数分析..........................................................................................................44 5.3.4 树脂药卷用量分析.................................................................................................44 5.4 实施过程 ........................................................................................................................46 5.5 实施效果分析 ................................................................................................................47 5.5.1 巷道围岩收敛监测..................................................................................................47 5.5.2 声波探测..................................................................................................................48 5.5.3 围岩钻孔窥视..........................................................................................................50 5.6 本章小结 .......................................................................................................................50 6 主要结论..............................................................................................................................51 致 谢..................................................................................................................................52 参考文献..................................................................................................................................53 附 录......................................................................................................................................55 1 绪论 1 1 绪论 1.1 问题的提出 软岩支护是国内外面临的重要研究课题，尽管前人在此领域已进行了大量的探讨， 取得了很多有价值的研究成果，但由于软岩受埋藏深度、赋存性状、水文地质、物相成 份及矿山压力等因素的影响，致使软岩表现出不同的流变特性，这给软岩控制带来了非 常大的困难。如清水营煤矿786m 水平井底车场因处在软岩内，经工程调研采取了“让 -抗”支护方案，但实施后已掘出巷段均发生了严重的变形破坏，后经修复加固也未取 得的有效控制。为此本文就以清水营煤矿786m 水平井底车场所处的软岩为研究对象， 探讨其变形破坏机理及影响因素，在此基础上采取相应的控制方案，该方案实施后再经 矿压监测及测试，验证其有效性，由此为清水营煤矿的软岩建立一种有效的控制方式。 1.2 研究意义 软岩除了自身强度低、节理裂隙发育及所含的不良物相成份外，但在其它外部因素 的影响下也会表现出不同的变形破坏特性， 如淋水浸泡将出现膨胀变形及相应的膨胀压 力；支护结构与软岩性状和矿压环境不相耦合将无法取得有效控制；软岩揭露后不及时 封闭将出现风化破碎；软岩若采用不等强支护会因应力集中而导致局部首先破坏，然后 波及到整个断面或巷道。 所以本文就以清水煤矿786m 水平井底车场所处的软岩为研究 对象， 除了进行力学性质试验和物相成份化验外， 还必须对各种外部影响因素进行分析， 然后建立与此环境相适应的支护结构，以取得有效控制，这对于清水营煤矿的软岩支护 将具有非常重要的现实意义和长远影响， 同时也对其它矿井的软岩支护具有良好的借鉴 和指导作用。 1.3 软岩巷道支护理论国内外研究现状 1.3.1 国外软岩巷道支护理论研究现状 国外以南非、波兰为代表的高应力软岩巷道支护技术研究从20世纪80年代初期开 始，其他国家如俄罗斯、澳大利亚、英国、德国、印度、日本等都进行过深部巷道支护 技术研究，大量研究成果及工程实践使软岩巷道支护技术有了比较系统、全面的发展， 各种支护理论和技术都得到了不断完善和推广。 20世纪初，Haim、Rankine、K.Terzaghi、太沙基、Fenner、Kastner、L.V.Rabcewicz 等在工程实践的基础上