大倾角中厚煤层坚硬顶板综采采场矿压规律研究.pdf

大倾角中厚煤层坚硬顶板综采采场 矿压规律研究 重庆大学硕士学位论文 （学术学位） 学生姓名王艳磊 指导教师唐建新 教 授 专 业采矿工程 学科门类工 学 重庆大学资源及环境科学学院 二 O 一五年四月 Study on mine pressure law of fully-mechanized stope with large inclined angle and hard roof in medium-thickness seam A Thesis ted to Chongqing University in Partial Fulfillment of the Requirement for the Master’Degree of Engineering By Wang Yanlei Supervised by Prof. Tang Jianxin SpecialtyMining Engineering College of Resources and Environmental Science of Chongqing University, Chongqing, China April, 2015 中文摘要 I 摘 要 与缓倾斜近水平煤层不同，大倾角煤层由于煤、岩层沉积结构的特殊性,导致 其具有显著的各向异性特征，且随倾角的增大，各向异性越明显，导致大倾角煤 层综采开采有其特殊的岩层运动规律和矿压显现特点。大倾角坚硬顶板采场和普 通采场的主要区别是矿山压力显现的不同，坚硬顶板采场其矿山压力显现更为剧 烈，且易发生冲击矿压。目前为止，我国在大倾角煤层开采过程中的回采工艺、 巷道围岩控制、上覆岩层运移规律、矿压显现规律等问题上进行了一定的理论和 实验研究， 取得了丰富的经验, 但对大倾角坚硬顶板工作面矿压显现规律的研究相 对较少。煤矿采场矿压研究中，坚硬顶板控制是一项重要研究内容。因此开展本 项目的研究有着重要的理论意义和工程应用价值。 本文以代池坝煤矿大倾角中厚煤层坚硬顶板 3（13）43 综采工作面为研究背 景，通过理论分析，数值模拟分析、现场实测数据分析等方法，对大倾角中厚煤 层坚硬顶板综采工作面的采场矿压分布规律、围岩应力状态、顶板垮落规律、支 架围岩关系等方面的内容进行了分析研究。论文取得的主要研究成果如下 ①理论分析、数值模拟和现场实测相结合，系统的研究了大倾角中厚煤层坚 硬顶板综采工作面的矿压显现规律，确定了直接顶和基本顶的初次和周期垮落步 距。 ②对代池坝 13 号煤层赋存状态进行矿压分析，结合液压支架的矿压观测，针 对其大倾角中厚煤层坚硬顶板情况，得出适合代池坝 3（13）43 综采工作面液压 支架的支护强度、加权平均支护强度参数。 ③通过对综采液压支架的工作阻力观察分析，得出顶板垮落规律，并对支架 的工作适应性、运行特性进行评价，为预测来压、改善工作面的安全环境，提高 支护质量提供依据。 ④在大倾角坚硬顶板情况下，采用预裂爆破强制放顶技术，人为缩短顶板初 次来压步距。通过数值模拟、理论分析与现场试验相结合的方法，验证了放顶技 术的合理性。 关键词关键词大倾角，中厚煤层，坚硬顶板，矿压规律，数值模拟，现场实测 重庆大学硕士学位论文 II 英文摘要 III ABSTRACT With the specificity of the sedimentary structure of coal seams and strata, deeply inclined coal seams are characterized by anisotropy, which are different from gently inclined flat seams. In addition, the characteristic related to anisotropy seems to be more obvious as the dip angle increases, and as a result, fully-mechanized mining with deeply inclined coal seam possesses special strata movement law and strata pressure behaviors. The main difference between stope with hard roof and ordinary stope is the distinct strata pressure behavior. Specifically, the strata pressure of the er one is more violent and it is easy to cause impulsion pressure.So far some certain theories and experiment researches relevant to mining technology, roadway surrounding rock control, movement law of overlying strata and strata pressure behavior of deeply inclined coal seam mining are conducted in China and abundant experience is obtained. However, the researches involved strata pressure behavior of working faces with large inclined angle and hard roof are relatively less. In the study of strata pressure of coal stope, hard roof control is a significant part. Thus, it is of great theoretic importance and has engineering application value to study this project. Based on the 31343 fully-mechanized face of hard roof of Daichiba mine with larege inclined angle and medium-thickness seam, theoretical analysis, numerical simulation and field measured data are applied in the paper to analyze the characteristics of fully-mechanized face of hard roof with large inclined angle and medium-thickness seam, including stope strata pressure distribution rule, surrounding rock stress state, roof caving law and relationship between support and surrounding rock. The main research findings are as follows ①Combined theoretical analysis with numerical simulation and field measurement, the strata pressure law of fully-mechanized face of hard roof with large inclined angle and medium-thickness seam is systematically studied to confirm the first and the periodic caving interval of immediate roof and basic roof. ②The strata pressure of occurrence of 13 coal seam in Daichiba Mine is analyzed in this paper. Combined with the mine pressure observation of hydraulic support, the conditions of large inclined angle, medium-thickness seam as well as hard roof are considered to obtain the parameters of support strength and weighted average support strength of 31343 fully-mechanized face. 重庆大学硕士学位论文 IV ③The support pressure of fully-mechanized hydraulic support is observed and analyzed to obtain the roof caving law. Moreover, the labor aptitude and operating feature of support are uated to provide basis for forecasting mine pressure, improving the safe surrounding of working face and enhancing support quality. ④Under the condition of large inclined angle and hard roof, presplitting blasting forcing caving technology is adopted to artificially shorten the first weighting interval of roof. And numerical simulation, theoretical analysis and field experiment are combined to validate the rationality of caving technology. KeywordsLarge inclination, Medium-thickness seam, Hard roof, Strata behavior regularity, Numerical simulation,Field measurement 目 录 V 目 录 中文摘要中文摘要 .......................................................................................................................................... I 英文摘要英文摘要 ....................................................................................................................................... III 1 绪绪 论论 ......................................................................................................................................... 1 1.1 选题背景及研究意义选题背景及研究意义 ............................................................................................................ 1 1.1.1 选题背景 .................................................................................................................... 1 1.1.2 研究意义 .................................................................................................................... 2 1.2 国内外研究现状国内外研究现状 ................................................................................................................... 2 1.2.1 国内外采场矿山压力理论研究现状 ........................................................................ 2 1.2.2 国内大倾角煤层开采研究现状 ................................................................................ 3 1.2.3 国外大倾角煤层开采研究现状 ................................................................................ 6 1.3 研究内容及技术路线研究内容及技术路线 ........................................................................................................... 7 1.3.1 研究内容 .................................................................................................................... 7 1.3.2 技术路线 .................................................................................................................... 8 2 大倾角坚硬顶板煤层围岩稳定性分析大倾角坚硬顶板煤层围岩稳定性分析 ................................................................... 9 2.1 大倾角煤层顶板岩层运动规律及矿压显现特征大倾角煤层顶板岩层运动规律及矿压显现特征 ............................................................... 9 2.1.1 顶板岩层运动规律 .................................................................................................... 9 2.1.2 矿压显现特点 .......................................................................................................... 11 2.1.3 坚硬顶板采场矿山压力显现特征 .......................................................................... 13 2.2 大倾角煤层顶板断裂岩块力学结构分析大倾角煤层顶板断裂岩块力学结构分析 ......................................................................... 14 2.2.1 倾斜砌体结构形式 .................................................................................................. 14 2.2.2 倾斜砌体结构的分布特征 ...................................................................................... 15 2.2.3 倾斜砌体结构的运动特征 ...................................................................................... 16 2.3 大倾角综采工作面支架工作阻力分析大倾角综采工作面支架工作阻力分析 ............................................................................. 17 2.3.1 支架工作阻力公式确定 .......................................................................................... 17 2.3.2 支架选型 .................................................................................................................. 19 2.4 本章小结本章小结 ............................................................................................................................. 21 3 大倾角坚硬顶板煤层采场围岩活动数值模拟研究大倾角坚硬顶板煤层采场围岩活动数值模拟研究 ....................................... 23 3.1 软件介绍软件介绍 ............................................................................................................................. 24 3.1.1 FLAC3D软件介绍 ..................................................................................................... 24 3.1.2 UDEC 软件介绍 ....................................................................................................... 24 3.2 数值模拟计算模型的建立数值模拟计算模型的建立 ................................................................................................. 25 重庆大学硕士学位论文 VI 3.2.1 工程地质概况 .......................................................................................................... 25 3.2.2 模型的设定原则 ...................................................................................................... 26 3.2.3 模型设定 .................................................................................................................. 27 3.2.4 岩石力学参数的选取 .............................................................................................. 29 3.2.5 坚硬顶板分类 .......................................................................................................... 30 3.3 数值模拟结果及分析数值模拟结果及分析 ......................................................................................................... 31 3.3.1 矿压规律分析 .......................................................................................................... 31 3.3.2 采空区自然垮落数值模拟 ...................................................................................... 50 3.3.3 使用放顶技术强制放顶数值模拟 .......................................................................... 56 3.4 大倾角坚硬顶板初次放顶预裂破顶技术大倾角坚硬顶板初次放顶预裂破顶技术 ......................................................................... 62 3.4.1 初次放顶预裂破顶炮眼眼孔布置 .......................................................................... 63 3.4.2 初次放顶预裂爆破程序 .......................................................................................... 65 3.4.3 预裂爆破效果分析 .................................................................................................. 65 3.5 本章小结本章小结 ............................................................................................................................. 65 4 矿压实测及其分析矿压实测及其分析 ............................................................................................................ 67 4.1 现场观测条件现场观测条件 ..................................................................................................................... 67 4.2 矿压观测方案矿压观测方案 ..................................................................................................................... 67 4.2.1 矿压观测目的 .......................................................................................................... 67 4.2.2 观测的主要内容 ...................................................................................................... 67 4.2.3 测点布置和观测方法 .............................................................................................. 67 4.3 矿压观测结果及分析矿压观测结果及分析 ......................................................................................................... 68 4.3.1 矿压观测结果 .......................................................................................................... 68 4.3.2 矿压观测结果分析 .................................................................................................. 71 4.3.3 支架适应性、运行特性评价 .................................................................................. 73 4.3.4 煤壁片帮状况 .......................................................................................................... 75 4.3.5 煤壁稳定性分析 ...................................................................................................... 76 4.4 本章小结本章小结 ............................................................................................................................. 78 5 综合分析综合分析 ................................................................................................................................. 79 5.1 理论综合分析理论综合分析 ..................................................................................................................... 79 5.1.1 大倾角坚硬顶板岩层运动规律分析 ...................................................................... 79 5.1.2 大倾角坚硬顶板矿压显现特征分析 ...................................................................... 79 5.2 数值模拟结果综合分析数值模拟结果综合分析 ..................................................................................................... 80 5.2.1 矿压规律分析 .......................................................................................................... 80 5.2.2 采空区顶板垮落数值模拟结果分析 ...................................................................... 80 目 录 VII 5.3 现场实测结果综合分析现场实测结果综合分析 ..................................................................................................... 82 5.4 本章小结本章小结 ............................................................................................................................. 82 6 主要结论主要结论 ................................................................................................................................. 83 致致 谢谢 ....................................................................................................................................... 85 参考文献参考文献 ....................................................................................................................................... 87 附附 录录 ....................................................................................................................................... 91 A.作者在攻读硕士学位期间发表的论文作者在攻读硕士学位期间发表的论文 ................................................................................ 91 重庆大学硕士学位论文 VIII 1 绪 论 1 1 绪 论 1.1 选题背景及研究意义 1.1.1 选题背景 随着世界经济全球化进程的推进，我国的经济发展正保持一种持续、平稳的增 长趋势。煤炭作为我国的主要能源，在国民经济建设中具有重要的战略地位，煤 炭工业是支承我国国民经济发展的重要基础工业。长期以来，煤炭在我国一次能 源生产和消费构成中比例始终保持在 70以上[1]。 根据研究预测， 我国未来一次能 源消费中煤炭仍将占据主导地位，即使到 2050 年，煤炭在我国一次能源消费结构 的比例也不会低于 35[2,3]。近年来，我国煤炭产量总体保持快速增长势头，我国 煤炭的生产和消费一直居世界第一位。根据专家预测，到 2020 年我国煤炭产量占 世界煤炭产量的比例会上升到 50左右[4]。因此,促进我国煤炭资源安全高效开采 对我国的国民经济快速稳定发展具有重要作用。 我国煤炭资源预测总量为 5.06 万亿吨,且呈现分布广泛、西多东少、埋藏较深、 煤层开采条件差等特点。近年来,大倾角煤层35 55 越来越引起采矿界的重视,主 要原因有 第一，西北部赋存有大量的 35 以上的大倾角煤层。我国煤田中急倾斜、大倾 角厚煤层所占比重较大,大约占煤炭总储存量的 14.05，特别在我国的西北地区的 山西、陕西、宁夏、甘肃和新疆等地,大倾角煤层为许多矿区或矿井的主采煤层。 目前，虽然大倾角煤层年开釆量仅占我国煤炭总产量的 810，但在一些地区 大倾角煤层年产量却占有非常大的比例，如四川省大约有 4050的煤炭产量为 大倾角煤层开采产量[5]。随着我国“十二五”计划中控制东部，稳定中部，大力发 展西部的煤炭发展战略，大倾角煤层开采问题的研究将是一项重大课题[6]。 第二，多年来的开采己使矿区赋存条件优越的煤层储量越来越少，因而转向了 煤层储量只占 1520大倾角或急倾斜煤层的开采上来。许多东部矿区，如安徽 的淮北和淮南矿区、江苏的徐州矿区、山东的兖州矿区、河北的邢台和开漆矿区 等，随着煤炭开采强度的日益提高，赋存条件优越的煤层越来越少，条件恶劣的 复杂煤层开采势在必行，特别是大倾角复杂条件下的煤层开采[7]。 若要保证大倾角复杂煤层的安全高效开采，就必须解决大倾角煤层开采过程 中的技术难题。因此，对影响因素多、物理过程复杂的大倾角煤层综采开采的关 键技术，尤其是矿山压力显现规律、围岩控制等问题，有必要进行进一步的深入 研究，这不仅具有重要的理论价值，而且对二十一世纪我国的能源战略、煤炭行 业可持续发展、大倾角矿山高产高效安全生产具有重大的经济效益和社会效益。 重庆大学硕士学位论文 2 1.1.2 研究意义 开采大倾角工作面上覆岩层运动规律和采场矿压显现规律与缓倾斜煤层开采 条件下有很大差别。对比一般缓倾斜开采，大倾角煤层被开采后，其上覆岩层运 动和破坏的影响范围将向采空区上部边界偏移