大尺度混凝土充填墙体高温致裂机理及降温技术研究.pdf
硕士学位论文 大尺度混凝土充填墙体高温致裂机理 及降温技术研究 Fissure Mechanism Induced by High Temperature and Cooling Approaches of Concrete Filling Walls with Large Scale 作 者王晓卿 导 师张农 教授 中国矿业大学 二○一四年五月 江苏省高校优势学科建设工程资助项目 国家自然科学基金资助项目51274193 江苏省基础研究计划资助项目BK2012570 万方数据 中图分类号 TD353 学校代码 10290 UDC 622 密 级 公开 中国矿业大学 硕士学位论文 大尺度混凝土充填墙体高温致裂机理 及降温技术研究 Fissure Mechanism Induced by High Temperature and Cooling Approaches of Concrete Filling Walls with Large Scale 作 者 王 晓 卿 导 师 张 农 教 授 申请学位 工学硕士 培养单位 矿业工程学院 学科专业 采矿工程 研究方向 巷道围岩控制 答辩委员会主席 李学华 评 阅 人 薛俊华 李桂臣 二○一四年五月 万方数据 73 学位论文原创性声明学位论文原创性声明 Declaration of Thesis Originality 本人郑重声明所呈交的学位论文大尺度混凝土充填墙体高温致裂机理及 降温技术研究 ,是本人在导师指导下,在中国矿业大学攻读学位期间进行的研 究工作所取得的成果。据我所知,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。 学位论文作者签名 年 月 日 万方数据 学位论文使用授权声明学位论文使用授权声明 Certificate of Thesis Authority 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 2014 年 月 日 2014 年 月 日 万方数据 论文审阅认定书 Thesis Approval Identification 研究生 王 晓 卿 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 万方数据 致致谢谢 Acknowledgements 本文是在导师张农教授的悉心指导下完成的,在论文选题、路线设计、框架 构建乃至最后的文理疏通、 审阅定稿等每一步工作中, 导师都倾注了大量的心血。 导师提供了现场实践的平台,并对试验给予了经费支持。此外,在我继续深造的 求学之路上,导师也给予了极大的鼓励和帮助。导师对学生认真负责的态度,严 谨求实的治学精神以及勤勉的工作作风是我今后学习和工作的榜样,师从三载, 受益终身。在此,谨向导师致以深深的敬意和由衷的感谢。 论文在开题和撰写过程中得到了阚甲广副教授、李桂臣副教授、郑西贵副教 授、 许兴亮副教授、 季明老师、 吴海老师、 赵一鸣老师、 韩昌良老师的悉心指导, 高明仕教授及安全工程学院李忠辉教授也给予了宝贵建议, 同时得到了李宝玉博 士、于宪阳博士、薛飞博士的热情帮助,在此一并表示诚挚的感谢。 特别感谢淮南矿业集团潘一东煤矿操新民副矿长,孙建国副总工程师、肖长 春副总工程师,生产技术部罗星刚副部长、孔翔技术员、赵立峰技术员、任启明 技术员在工程实践过程中提供的现场协调与支持。 感谢课题组史英男、王逸凡、武精科、潘东江、徐绍武等硕士在现场测温过 程中付出的辛勤劳动,感谢东南大学郭丽萍副教授、 张丽辉硕士在充填材料水化 热测定试验中提供的帮助, 感谢深部岩土力学与地下工程国家重点实验荆玉明硕 士、 白东峰硕士在数值计算过程中提出的建议,正是由于他们的协助才得以获得 准确充分的支撑材料。 感谢谷学远、魏振亮、姚新盼、张云凯、张彦龙、赵永卓、董抗抗、曹振兴、 裴宗远等朋友在硕士求学生涯中给予的接济,得以保证宽松的经济条件。感谢甘 建东、曹明、杨增强在生活上给予的帮助,同窗七年,共筑终生友谊。感谢姚亚 虎、王龙江、陈瑶、姜凯、孙辉、刘洪洋、王彬、张志义、张明等硕士求学三年 的陪伴,习学共进,觥筹把欢,而今欲别,感慨萦于心间,愿他们前程似锦。 慈鸦还哺,羔羊跪乳,父母恩情,终身难报。我今年二十又五,尚无尺寸之 功于父母,且多受其接济,每念及此,深感惭愧。此外,感谢哥哥、姐姐及女友 在我求学路上给予的关心与支持。衷心祝他们身体健康,生活幸福 最后感谢在百忙之中评审论文并提出宝贵意见的各位专家, 感谢论文所有引 用文献作者们的辛勤工作,感谢所有帮助和关心过我的人 王晓卿 2014 年 5 月于徐州 万方数据 I 摘要摘要 充填墙体因高温引起的系列问题制约了沿空留巷技术在深部卸压开采中的 应用,本文为解决这一问题,立足充填墙体的特殊性,综合运用了理论分析、现 场实测、实验室试验及数值模拟等手段,先后研究了充填墙体高温的原因、高温 的演化规律及充填墙体在温度应力及采动应力耦合作用下的破坏过程与机理, 并 以此为基础,提出了切实可行的降温技术。得到的主要结论如下 (1)分析了充填墙体高温对回采的影响。致使墙体出现片落及开裂等破坏 现象,影响墙体承载能力;恶化工人作业环境,影响工人健康;引发采空区遗煤 自燃及瓦斯爆炸。 (2)阐述了充填墙体高温的原因。大埋深高地热、大功率采掘装备发热、 充填材料水化热及混凝土较差的导热性引起了充填墙体内部的高温, 而且高温程 度较地面大体积混凝土更为剧烈。 水化热测定试验表明 CHCT 充填材料 3 d 内的 放热量高达总放热量的 75.2,远大于普通水泥材料的 30。 (3) 通过理论推导、 实测及数值模拟手段研究了充填墙体高温的演化规律。 充填墙体内部在第 5 d 时达到最高温度 60.9 ℃;墙体表面在第 2.5 d 时达到最高 温度 40.4 ℃;墙体内外的最大温差出现在第 5 d,为 22.0 ℃,从第 3.5 d 到第 7 d 温差一直在 20.0 ℃以上。 (4)探讨了充填墙体耦合破坏过程及机理。温度应力使充填墙体表面产生 温度裂缝。充填墙体滞后工作面受采动应力影响显著,在温度应力及采动应力耦 合作用下,温度裂缝向墙体深部延深,最终发展成为贯穿裂缝。模拟表明,在温 度应力单独作用下,第 5 d 时墙体表面出现温度裂缝。附加采动应力后,裂缝不 断延深,当采动应力为 16 MPa 时,墙体发生耦合破坏。因此应控制充填墙体所 受采动应力不超过 16 MPa。 (5)提出充填墙体降温技术途径,包括降低混凝土入模温度和墙体同步降 温技术。降低混凝土入模温度应充分利用矿井降温系统。 墙体同步降温技术采用 内部埋管通水及表面喷头洒水相配合的方式, 并进行了详细的参数设计与可行性 分析,表明该技术在技术及经济方面均可行。 论文共有图 49 幅,表 12 个,参考文献 77 篇。 关键词关键词沿空留巷;充填墙体;高温;充填材料;水化热;降温技术 万方数据 III Abstract A series of problems of filling walls caused by high temperature have already restricted the application of gob-side entry retaining in deep stress-releasing mining. To solve this problem, this paper studied the reasons and evolution law of high temperature and failure mechanism of filling walls under coupling effect of both thermal stress and mine-induced stress with integrated s of theoretical analysis, field measurement, laboratory tests and numerical simulation. Then on this basis, practicable cooling approaches were put forward. Main conclusions are as follows 1 High temperature of filling walls has serious impacts on mining , not only can cause wall deation including flaking and cracking which would influence the bearing capacity of filling walls, but also deteriorates working environment of mines, and creates hazards of residual coal self-ignition and gas explosion in gob. 2 The high temperature reasons of filling walls were described. The high temperature inside the filling walls was caused by high geothermal induced by large buried depth, heat released by high-power mining equipment, massive hydration heat produced by filling materials and poor thermal conductivity of concrete, with the high temperature degree more intense than ground mass concrete. Hydration heat determination experimental results show that the value of hydration heat released within 3 days of CHCT filling materials was measured up to 75.2 of the total heat, much larger than 30 of ordinary cement materials. 3 The evolution law of high temperature was studied through theoretical analysis, measurement and numerical simulation. The inner parts of filling walls reach the highest temperature 60.9 ℃ on the 5th day while the surface parts reach the highest temperature 40.4 ℃ on the 2.5th day. The maximum temperature difference between the inside and outside wall is 22.0 ℃ on the 5th day and the temperature difference has been above 20.0 ℃ from the 5th day to the 7th day. 4 Coupling failure process and mechanism of filling walls were studied. Thermal stress exceeding the allowable stress leads to temperature cracks on the filling walls surface. Filling walls are significantly affected behind working face by mining-induced stress. Under the coupling effect of thermal stress and mining-induced stress, thermal cracks extend into interior of filling walls and eventually develop into through cracks, resulting in coupling failure. Simulation shows that cracks occur on the 5th day under the single effect of thermal stress. With the addition of mining-induced stress, cracks constantly extend. When 万方数据 IV mining-induced stress increases to 16 MPa, filling walls occur coupling failure. So the mining-induced stress should be controlled not more than 16 MPa. 5 Filling walls cooling approaches were proposed, including lowering the temperature of fresh concrete and synchronous filling wall cooling approach, which combines internal water transportation through embedded pipe and surface nozzle water spraying. Lowering the temperature of fresh concrete should make full use of mine air-conditioning system. Detailed principles and parameters design, and field application feasibility analysis were carried out for synchronous filling wall cooling approach, indicating that the approach is feasible, both in the technical and economic aspects. This paper has together 49 figures, 12 tables and 77 references quoted. Keywords gob-side entry retaining; filling walls; high temperature; filing materials; hydration heat; cooling approaches 万方数据 V 目录目录 摘要摘要 ............................................................................................................................... I 目录目录 .............................................................................................................................. V 图清单图清单 ........................................................................................................................ IX 表清单表清单 ........................................................................................................................ XI 变量注释表变量注释表 ............................................................................................................. XIII 1 绪论绪论 ........................................................................................................................... 1 1.1 问题提出与研究意义............................................................................................. 1 1.2 国内外研究现状..................................................................................................... 2 1.3 研究内容及技术路线............................................................................................. 8 2 充填材料水化热测定及充填材料水化热测定及充填墙体高温原因分析充填墙体高温原因分析 ................................................. 10 2.1 充填墙体概况....................................................................................................... 10 2.2 充填材料水化热测定........................................................................................... 15 2.3 充填墙体高温原因分析....................................................................................... 24 2.4 本章小结............................................................................................................... 26 3 沿空留巷充填墙体沿空留巷充填墙体高温高温量化量化研究研究 ......................................................................... 28 3.1 充填墙体高温实测............................................................................................... 28 3.2 充填墙体高温理论计算....................................................................................... 31 3.3 充填墙体高温数值模拟....................................................................................... 33 3.4 本章小结............................................................................................................... 40 4 温度应力及采动应力耦合作用下充填墙体破坏机理温度应力及采动应力耦合作用下充填墙体破坏机理 ......................................... 41 4.1 充填墙体温度裂缝产生的判据........................................................................... 41 4.2 充填墙体耦合破坏过程探讨............................................................................... 43 4.3 充填墙体耦合破坏数值模拟............................................................................... 46 4.4 本章小结............................................................................................................... 51 5 沿空留巷充填墙体降温技术沿空留巷充填墙体降温技术 ................................................................................. 52 5.1 充填墙体防裂分析............................................................................................... 52 5.2 充填墙体降温途径............................................................................................... 54 5.3 充填墙体同步降温技术....................................................................................... 55 5.4 本章小结............................................................................................................... 58 6 主要结论主要结论 ................................................................................................................. 59 参考文献参考文献 ..................................................................................................................... 61 万方数据 VI 附录附录 ............................................................................................................................. 65 作者简历作者简历 ..................................................................................................................... 71 学位论文原创性声明学位论文原创性声明 ................................................................................................. 73 学位论文数据集学位论文数据集 ......................................................................................................... 75 万方数据 VII Contents Abstract ...................................................................................................................... III Contents .................................................................................................................... VII List of Figures ............................................................................................................ IX List of Tables .............................................................................................................. XI List of Variables...................................................................................................... XIII 1 Introduction ............................................................................................................... 1 1.1 The Raising of Problem and Meaning of Research ................................................. 1 1.2 Current Situation of the Research at Home and Abroad .......................................... 2 1.3 Research Contents and s .............................................................................. 8 2 Hydration Heat Determination of Filling Materials and High Temperature Reasons Analysis of Filling Walls ............................................................................. 10 2.1 General Situation of Filling Walls ......................................................................... 10 2.2 Hydration Heat Determination of Filling Materials ............................................... 15 2.3 High Temperature Reasons Analysis of Filling Walls ........................................... 24 2.4 Brief Summary ....................................................................................................... 26 3 High Temperature Quantization of Filling Walls in Gob-side Entry Retaining28 3.1 High Temperature Measurement of Filling Walls .................................................. 28 3.2 High Temperature Theoretical Calculation of Filling Walls .................................. 31 3.3 High Temperature Numerical Simulation of Filling Walls .................................... 33 3.4 Brief Summary ....................................................................................................... 40 4 Failure Mechanism of Filling Walls under Coupling Effect of Both Thermal Stress and Mining-induced Stress ............................................................................ 41 4.1 The Criterion for Generation of Temperature Crack on Filling Walls ................... 41 4.2 Coupling Failure Process of Filling Walls ............................................................. 43 4.3 Numerical Simulation of Coupling Failure of Filling Walls .................................. 46 4.4 Brief Summary ....................................................................................................... 51 5 Cooling Approaches of Filling Walls in Gob-side Entry Retaining .................... 52 5.1 Analysis of Crack Control of Filling Walls ............................................................ 52 5.2 Cooling Ways of Filling Walls ............................................................................... 54 5.3 Filling Walls Synchronous Cooling Approach ....................................................... 55 5.4 Brief Summary ....................................................................................................... 58 6 Main Conclusions .................................................................................................... 59 Reference .......................................................................