充填体—围岩协调变形机制与沿空留巷技术研究.pdf

博士学位论文 充填体-围岩协调变形机制与沿空留巷 技术研究 Research on Compatible Deation Mechanism Between Backfill Body-Surrounding Rock and Gob-side Entry Retaining Technology 作者周保精 导师徐金海 中国矿业大学 二○一二年五月 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 中图分类号 TD353 学校代码 10290 UDC 622 密 级 公开 中国矿业大学 博士学位论文 充填体-围岩协调变形机制与沿空留巷 技术研究 Research on Compatible Deation Mechanism Between Backfill Body-Surrounding Rock and Gob-side Entry Retaining Technology 作 者 周保精 导 师 徐金海 申请学位 工学博士 培养单位 矿业工程学院 学科专业 采矿工程 研究方向 矿山压力与岩层控制 答辩委员会主席 评 阅 人 二○一二年三月 论文审阅认定书论文审阅认定书 Thesis approval identification 研究生 周保精 在规定的学习年限内，按照研究生培养方案的 要求，完成了研究生课程的学习，成绩合格；在我的指导下完成本学 位论文,经审阅，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， 同意将本论文作为学位申请论文送 专家评审。 导师签字 年 月 日 致谢致谢 Acknowledgments 呈上论文之际，首先呈上我对恩师徐金海教授的深深谢意 来到导师身边已经五载，在导师的言传身教中，我学到了许多做人、做事、 做学问的道理。导师高尚的人格品质，深厚的学术造诣，严谨的治学态度，忘我 的工作精神，将是学生一生学习的榜样论文从选题、思路到成稿，一字一句无 不饱含着导师的心血，在论文完成之际，对徐金海老师的感激之情难以言表，唯 有在未来的工作中以自己的所学为煤炭事业多做贡献不愧于老师的教导恩情 论文撰写过程中有幸得到德高望重的茅献彪教授的指导和关怀，对论文的 结构、思路和方向的确定，给予了极大的帮助与支持，在此表示由衷的谢意 感谢我的同学许兴亮和沈荣喜在论文撰写过程中对我的关心、支持和鼓励， 我们的兄弟感情让我铭记在心 感谢矿业工程学院各位领导和老师的敦敦教诲、殷殷期望，并希望在今后 的学习和工作中，能够继续得到各位老师的指导和帮助 研究生的学习和生活中，得到了课题组各位教师和师兄弟的真诚帮助和鼎 力支持，在此向李冲博士、吴锐博士、马钱钱硕士、满在山硕士、张森硕士、何 清源硕士、秦帅硕士、王中亮硕士以及力建学院倪海敏硕士、李明硕士、李凯硕 士、马超硕士等表示深深的谢意 感谢父母，他们含辛茹苦地把我养大，并对我辞职考博士给予大力支持， 他们对我的付出是我一辈子都报答不尽的，衷心地希望他们身体健康 感谢我的 妻子、儿子，是由于她们对我的理解、关心和支持我才得以完成攻读博士学位的 学业。 感谢各位评审专家在百忙之中的不吝指导，感谢论文所引用文献作者的辛 勤工作，感谢所有曾经帮助和关心过我的人 周保精 2012 年 3 月于徐州 I 摘摘 要要 在煤矿生产中，回采巷道的长度约占巷道总长度的 60以上，采用沿空留 巷技术可以解决煤柱损失问题， 提高煤炭回收率， 还可以达到有效治理工作面生 产中瓦斯超限问题。 因此， 采用沿空留巷无煤柱护巷开采方法符合我国科学采矿、 绿色采矿的发展方向。 在沿空留巷施工中巷旁支护充填体的稳定是沿空留巷成功 的主要影响因素之一， 由于巷旁支护充填体经历顶板活动持续时间长、 产生应力 集中度高、动压影响强烈，因此，保持充填体的稳定存在诸多不确定因素，充填 体的破坏失稳是造成沿空留巷失败的主要原因之一。 本论文采用理论分析、 模拟计算、 实验室实验和现场工业性试验等多种手段 相结合的方法，系统研究了留巷顶板与充填体相互作用机理、充填体-围岩协调 变形机理、 软介质接顶充填体应力均布效果、 以及软介质接顶充填体和冒落矸石 胶结固化充填体的稳定性， 并在工业性试验中取得了十分满意的效果。 主要研究 成果如下 （1）将充填体、接顶软介质和顶板简化成不同刚性系数 Δbb Ea k - 的等效 弹簧， 根据充填体和顶板相互作用机理， 顶板与充填体之间应力与变形关系以及 充填体适应顶板支护要求， 通过充填体强度参数设计来实现老顶、 直接顶与充填 体之间协调变形。 （2）根据倾斜煤层采空区冒落矸石自溜的规律，充分利用采空区冒落矸石 作为主要沿空留巷巷旁充填主要材料，通过喷浆、 灌浆固化提高充填体抗压强度 和整体稳定性，成功实现倾斜煤层沿空留巷。 （3） 突破传统充填体宽高比系数不小于 0.8 的要求， 采用宽高比系数为 0.23 的软介质接顶胶结材料充填体成功沿空留巷， 这是在充填体力学性能和沿空留巷 系统结构稳定性方面一次新的探索和实践。 （4）在胶结材料充填体沿空留巷施工中，根据理论分析、计算采用柔性材 料接顶适应了老顶大结构的给定变形，并在充填体上方实现应力均布效果， 降低 了充填体边界顶板“旋转下沉”和横向位移在充填体上产生的应力集中，提高充 填体的稳定性。 上述研究成果在攀煤集团四个生产矿井的 45以下复杂产状煤层工作面中 得以成功应用。 关键词关键词协调变形；软介质接顶；充填体；冒落矸石；挡矸体系 III Abstract The length of mining roadway account for over 60 of the length of all roadways in coal mining production. Using the gob-side entry retaining technology can solve the problem about coal pillar loss, improve coal recovery and govern the gas ultralimit problem in workface production. Therefore, using the gob-side entry retaining technology with no coal pillars protection accords with development direction of mining scientifically and greenly in our country. The stability of roadway support backfill in the construction of gob-side entry retaining is one of the main influence factors which contribute to the success of gob-side entry retaining. The roadway support backfill experiences a long period of sustainable roof activities, gets a high stress concentration degree and is under a serious dynamic pressure influence, thus there exists several uncertain factors which relate to the stability of backfill, the failure and instability of backfill is one of the main causes which give rise to the failure of gob-side entry retaining. In this paper, we utilize the which combines theoretical analysis, stimulation calculation, laboratory experiment ,industrial field test and many other means, study systematically the interaction mechanism of the roof of gob-side entry retaining roadway and the backfill, the coordinated deation mechanism of the surrounding rock and the backfill, the even stress distribution effect of the backfill which is used in roof –contacted filling with soft media and the stability of the backfill roof-contacted with soft media and the caving gangue cementation solidification backfill. We acquire very decent effect in the industrial field test. The principal results are as follows 1 We simplify the backfill, the roof-contacted soft media and the roof to equivalent spring with various rigidity coefficients Δbb Ea k - . According to the interaction mechanism of the backfill and the roof, the stress and deation relationship between the roof and the backfill and the demand for backfill to adapt to roof support, we implement the coordinated deation between the main roof, the immediate roof and the backfill through designing the strength parameters of the backfill. 2 According to the law that caving gangue flows in inclined coal seam goaf, we make full use of the caving gangue in goaf as main backfill material on gob-side entry retaining roadway and implement successfully gob-side entry retaining in incline coal seam through gunite and grouting solidification to improve the compressive strength and the global stability of the backfill. 3 We break the requirement of the ratio of width and height of traditional backfill is not less than 0.8 and use the cementation material backfill with soft media roof-contacted which has a ratio of width and height accounting to 0.23. It is a new explores and practice for the mechanical properties of backfill and the stable factors about gob-side entry retaining system. 4 In the construction of the gob-side entry retaining with cementation material backfill, we adopt flexible material for roof-contaction to adapt to the given IV deation from the main roof large structure and implement the even stress distribution effect over the backfill, reduce the stress concentration, which caused by ‘rotation and subsidence’ of the roof at the boundary of the backfill and transverse displacement, on the backfill. We also improve the stability of the backfill. The above research results have been applied successfully in 4 working faces in complex occurrence coal seam, whose dip angle is less than 45, in Panmei Group Company. Keywords coordinated deation; roof-contacted with soft media; backfill; caving gangue; retaining gangue system. V Extended Abstract The length of mining roadway account for over 60 of the length of all roadways in coal mining production. Using the gob-side entry retaining technology can solve the problem about coal pillar loss, improve coal recovery and govern the gas ultralimit problem in workface production. Therefore, using the gob-side entry retaining technology with no coal pillars protection accords with development direction of mining scientifically and greenly in our country. The stability of roadway support backfill in the construction of gob-side entry retaining is one of the main influence factors which contribute to the success of gob-side entry retaining. The roadway support backfill experiences a long period of sustainable roof activities, gets a high stress concentration degree and is under a serious dynamic pressure influence, thus there exists several uncertain factors which relate to the stability of backfill, the failure and instability of backfill is one of the main causes which give rise to the failure of gob-side entry retaining. In this paper, we utilize the which combines theoretical analysis, stimulation calculation, laboratory experiment ,industrial field test and many other means, study systematically the interaction mechanism of the roof of gob-side entry retaining roadway and the backfill, the coordinated deation mechanism of the surrounding rock and the backfill, the even stress distribution effect of the backfill which is used in roof –contacted filling with soft media and the stability of the backfill roof-contacted with soft media and the caving gangue cementation solidification backfill. We acquire very decent effect in the industrial field test. The principal results are as follows 1 We simplify the backfill, the roof-contacted soft media and the roof to equivalent spring with various rigidity coefficients Δbb Ea k - . According to the interaction mechanism of the backfill and the roof, the stress and deation relationship between the roof and the backfill and the demand for backfill to adapt to roof support, we implement the coordinated deation between the main roof, the immediate roof and the backfill through designing the strength parameters of the backfill. 2 In the backfill roof-contacted with soft media structure, the soft media which used in roof-contaction cooperates with higher strength cementation material backfill to avoid the defect which contributes to the support ability of the cementation material backfill decreases rapidly after destroyed. This also enables the backfill roof-contacted with soft media to get high strength in early stage and increase resistance fast and constantly. 3 Through numerical simulation analysis, we realize that it is the stress concentration which can be easily caused by ‘rotation and subsidence’ of the roof at the boundary of the backfill and transverse displacement that result in backfill splitting failure and instability. After adopting soft media to roof-contaction, we achieve the effect that the stress above the backfill distributes evenly, the inside VI vertical stress above the backfill drops by nearly 4MPa. On the premise that the support for the roof is enough, the narrower the soft media is, the better the backfill yield effect would be. 4 Taking advantage of the feature that caving gangue flows in inclined coal seam goaf, we reserve caving gangue in the rise side of the roadway as main backfill material by the combined action of the flexible retaining gangue system and the rigid retaining gangue system. We stable gob-side entry retaining backfill through gunite and grouting solidification and precede the construction of gob-side entry retaining on working face in big inclined cola seam. 5 According to Rankine earth pressure mechanical analysis theory and calculation analysis, caving gangue backfill can maintain it stability under the condition in which the height is less than 2.5m and the dip angle is less than 45 when only external gunite is adopted. After adopting grouting solidification, the compressive strength of the backfill is improved and the stability of the backfill is enhanced further. 6 In order to control the abscission layer deation of the retained roadway roof, we use bolts and anchors to strengthen the roadway roof and the coal side which decreases the amount of bed separation between the immediate roof and the main roof efficiently and reduces squat in the roadway roof. Maintaining the integrity of the surrounding rock of roadway roof is one of the key factors which ensure the overall stability of the surrounding rock of roadway. The above research results have been applied successfully in 4 working faces in complex occurrence coal seam, whose dip angle is less than 45, in Panmei Group Company. Keywords coordinated deation; roof-contacted with soft media; backfill; caving gangue; retaining gangue system. VII 目目 录录 摘摘 要要........................................................................................................................ I I 目目 录录.................................................................................................................... VIIVII 图清单图清单...................................................................................................................... XIXI 表清单表清单.................................................................................................................... XVIXVI 变量注释表变量注释表........................................................................................................ XVIIIXVIII 1 1 绪论绪论........................................................................................................................ 1 1 1.1 研究背景及意义 .................................................1 1.2 国内外研究现状 .................................................4 1.3 研究内容与研究方法 .............................................8 2 2 沿空留巷围岩控制技术分析沿空留巷围岩控制技术分析 .............................................................................. 1111 2.1 沿空留巷顶板岩层运动特点 ......................................11 2.2 沿空留巷失效类型分析 ..........................................13 2.3 充填体的基本功能 ..............................................13 2.4 影响沿空留巷围岩稳定性的因素及控制技术 ........................14 2.5 本章小结 ......................................................16 3 3 充填体充填体- -围岩协调变形巷旁支护机理围岩协调变形巷旁支护机理 ................................................................ 1717 3.1 沿空留巷顶板与充填体相互作用机理 ..............................17 3.2 软介质接顶充填体支护机理 ......................................21 3.3 胶结加固冒落矸石充填体支护机理 ................................33 3.4 本章小结 ......................................................38 4 4 复杂产状煤层工作面沿空留巷围岩稳定性分析复杂产状煤层工作面沿空留巷围岩稳定性分析 .............................................. 4040 4.1 软介质接顶充填体整体稳定性分析 ................................40 4.2 软介质接顶结构稳定性数值分析 ..................................42 4.3 冒落矸石自然充填结构稳定性分析 ................................52 4.4 冒落矸石充填体围岩结构稳定性数值模拟分析 ......................54 4.5 本章小结 ......................................................59 5 5 复杂产状煤层工作面沿空留巷技术复杂产状煤层工作面沿空留巷技术 ................................................................. . 6060 5.1 充填体支护性能参数分析 ........................................60 5.2 留巷顶板围岩离层变形控制技术 ..................................62 VIII 5.3 软介质接顶充填体稳定性控制技术 ................................64 5.4 冒落矸石自然充填胶结固化技术 ..................................71 5.5 本章小结 ......................................................76 6 6 工业性试验工业性试验.......................................................................................................... 7777 6.1 试验矿区煤层地质条件 ...........................................77 6.2 软介质接顶沿空留巷技术应用 .....................................78 6.3 破碎矸石自然充填沿空留巷技术应用 ...............................87 6.4 本章小结 ......................................................99 7 7 主要结论及展望主要结论及展望 ................................................................................................ 100100 7.1 主要结论 .....................................................100 7.2 创新点 .......................................................101 7.3 展望 .........................................................101 作者简历作者简历................................................................................................................ 113113 学位论文原创性声明学位论文原创性声明 ...............