急倾斜俯伪斜采场顶板破断特征及矿压规律研究.pdf
急倾斜俯伪斜采场顶板破断特征 及矿压规律研究 重庆大学硕士学位论文 (专业学位) 学生姓名房 局 指导教师李 勇 副教授 兼职导师黄昌文 教授级高工 学位类别工程硕士(矿业工程) 重庆大学资源及环境科学学院 二 O 一八年四月 万方数据 万方数据 Research on Roof Breaking Characteristics and Law of Mine Pressure in Steep Bow Pseudo-Inclined Seam A Thesis ted to Chongqing University In Partial Fulfillment of the Requirement for the Professional Degree By Fang Ju Supervised by Associate Prof. Li Yong Pluralistic Supervised by Sn.Engr. Huang Changwen SpecialtyME Mineral Engineering College of Resources and Environmental Science of Chongqing University,Chongqing,China April,2018 万方数据 万方数据 中文摘要 I 摘 要 与近水平、缓倾斜煤层相比,急倾斜煤层由于煤层倾角大且开采后垮落矸石 的非均匀充填作用决定了其顶板破断特征及采场矿压规律的特殊性。本论文以逢 春煤矿 S2611 试验工作面为研究对象, 对急倾斜俯伪斜采场工作面顶板破断特征 及矿压规律进行了理论分析、数值模拟和现场矿压实测的研究,并对试验工作面 液压支架进行了适应性分析及运行特性评价,验证了 ZJY2400/8.5/15.5 支架能够 满足控制顶板的要求。主要研究工作、内容及结论为 ①建立急倾斜俯伪斜工作面顶板的梁式模型,分析了工作面顶板的破断特 征沿工作面推进方向上,上部水平顶板会首先发生断裂,然后中部、下部水平 顶板相继发生断裂,表现出时空差异特征;顺工作面倾斜方向上,在顶板两端发 生断裂后,中上部位置处顶板会首先发生断裂,顶板沿倾斜方向形成相对较稳定 的铰接结构。 ②将急倾斜俯伪斜采场悬露顶板简化为求解均布荷载作用下的矩形板,通过 求解矩形采场顶板,分析了均布荷载作用下顶板岩层在初次垮落和周期垮落前内 应力分布规律,并计算得到了顶板岩层上板面和下板面的最大主应力云图,分析 了顶板的破断形态为“O-X”和“C-X”型破坏。在此基础上预测了急倾斜俯伪 斜采场平行四边形顶板呈现倾斜“O-X”的初次破断及倾斜“C-X”型的周期破 断形态。 ③采用 FLAC3D软件构建了 S2611 急倾斜俯伪斜工作面数值计算模型,研究 沿煤层走向方向、顺工作面倾斜方向上采场矿压特征。得到了沿工作面推进方向 和顺工作面倾斜方向上不同推进距离情况下的垂直应力分布及演化特征;通过简 化模型,模拟分析了平行四边形采场顶板在均布荷载及非均布荷载条件下的破坏 特征。 ④通过对 S2611 试验工作面现场 10、27、44支架监测结果表明,采场工 作面倾斜方向下部顶板初次来压步距最小、上部顶板初次来压步距次之,中部顶 板初次来压步距最大;工作面顶板发生分段周期性断裂,平均周期来压步距是工 作面上部最小,中部次之,下部最大,上部、中部、下部之间的周期来压步距之 间均相差约 11。 ⑤基于理论计算及现场实测支架支护阻力,得到 ZJY2400/8.5/15.5 新型掩护 式液压支架对急倾斜薄煤层中等稳定及以下顶板有很强的适应性;对工作面支架 运行特性进行了评价, 最大工作阻力小于支架的额定工作阻力。 ZJY2400/8.5/15.5 新型液压支架能够很好的适应控制工作面顶板的要求。 关键词关键词急倾斜,俯伪斜,顶板破断,矿压规律,数值模拟,现场实测 万方数据 重庆大学硕士学位论文 II 万方数据 英文摘要 III ABSTRACT Different from the near horizontal and gently inclined coal seams, the characteristics of the roof breaking and the regularity of the mining pressure are determined by the large dip angle of the coal seam and the non uni filling of the collapsed gangue after mining. This paper is based on the characteristics of S2611 test face in Fengchun Coal Mine adopting the steep inclined pseudo-skewed arrangement. The theoretical analysis, numerical simulation and on-site measurement of mine pressure in the working face of the working face of the stope are carried out and tested. The hydraulic support of the working face was subjected to adaptive analysis and uation of the operating characteristics, verifying that the ZJY2400/8.5/15.5 support can meet the requirements for controlling the top plate. The main research contents and conclusions are as folloes ①The beam model of the top plate of the steeply inclined and inclined plane was established to analyze the breaking characteristics of the top plate of the working face along the direction of advancement of the working face, the upper roof would break first, and then the middle and lower roof phases would break, showing the spatiotemporal difference Features; Along the oblique direction of the work surface, after the two ends of the top plate break, the top middle plate will break first, and the top plate s a relatively stable hinge structure along the oblique direction. ②The suspended roof of steep inclined oblique stope is simplified to solve the rectangular plate subjected to uni load. By solving the top plate of rectangular stope, the internal forces of the roof rock strata under uni load before the initial collapse and periodic collapse are analyzed. According to the stress distribution law, the maximum principal stress cloud diagrams of the upper and lower slabs of the roof rock are calculated, and the broken patterns of the roof slabs are analyzed as “OX“ and “CX“ type damages. Based on this, it is predicted that the parallelogram roof of the steeply inclined and pre-diagonal mining slope exhibits the initial fracture of “O-X“ and the cyclical fracture pattern of “C-X“. ③The FLAC3D software was used to construct a numerical calculation model of S2611 steeply inclined pseudo-sloping face, and the strata pressure along the strike direction of the coal seam and the direction of the inclined face was studied. The 万方数据 重庆大学硕士学位论文 IV simulation results analyze the vertical stress distribution characteristics along the advancement direction of the working face and along the inclined direction of the working face. Through the simplified model, the parallelogram square roof is simulated and analyzed under the conditions of uni load and non-uni load. Breaking features. ④The monitoring results of the 10, 27, and 44 supports on the S2611 working face show that the top working face of the working face has the smallest initial pressing step, the upper working face, and the largest middle working face; the top face of the working face undergoes segmentation cycle Spontaneous fracture, the average cycle pressure step is the top of the work surface, followed by the middle, the lower part of the largest, the cycle between the upper, middle and lower pressure step difference are 11. ⑤Based on the theoretical calculations and on-site measurement of the support resistance of the support, the ZJY2400/8.5/15.5 shielded hydraulic support is highly adaptable to moderately stabilizing the steeply inclined thin seam and the following roof; the operating characteristics of the face support are uated and the maximum work is pered. The resistance is less than the rated working resistance of the bracket. It shows that the new hydraulic support of ZJY2400/8.5/15.5 can be well adapted to the requirements of the control roof. Key words Steeply inclined; Obliquely inclined; Roof breaking; Strata behavior regularity; Numerical simulation; Field measurement. 万方数据 目 录 V 目 录 中文摘要中文摘要 .......................................................................................................................................... I 英英文摘要文摘要 ....................................................................................................................................... III 1 绪绪 论论 ......................................................................................................................................... 1 1.1 研究背景及意义研究背景及意义 ................................................................................................................... 1 1.2 国内外研究现状国内外研究现状 ................................................................................................................... 1 1.2.1 采场矿山压力理论国内外的研究现状 ..................................................................... 1 1.2.2 急倾斜煤层顶板破断与矿压显现规律的相关研究 ................................................. 4 1.3 研究内容及技术路线研究内容及技术路线 ........................................................................................................... 6 1.3.1 研究内容 ................................................................................................................... 6 1.3.2 技术路线 ................................................................................................................... 7 2 急倾斜俯伪斜采场顶板破断理论分析急倾斜俯伪斜采场顶板破断理论分析 ................................................................... 9 2.1 引言引言 ....................................................................................................................................... 9 2.2 急倾斜俯伪斜采场急倾斜俯伪斜采场顶板破断力学分析顶板破断力学分析 ............................................................................. 10 2.2.1 急倾斜俯伪斜采场顶板破断的梁模型 .................................................................. 11 2.2.2 急倾斜俯伪斜采场顶板梁式破断特征分析 ........................................................... 14 2.3 采场顶板破断规律研究采场顶板破断规律研究 ..................................................................................................... 18 2.3.1 基本顶薄板模型求解.............................................................................................. 19 2.3.2 均布荷载作用下采场顶板岩层内力分布规律 ...................................................... 21 2.3.3 采场顶板破断规律 ................................................................................................. 24 2.4 本章小结本章小结 ............................................................................................................................. 27 3 急倾斜俯伪斜采场矿压规律数值模拟分析急倾斜俯伪斜采场矿压规律数值模拟分析 ....................................................... 29 3.1 引言引言 ..................................................................................................................................... 29 3.2 工程背景工程背景 ............................................................................................................................. 29 3.2.1 工作面概况 ............................................................................................................. 29 3.2.2 煤层赋存情况 ......................................................................................................... 30 3.3 急倾斜俯伪斜采场矿压规律模拟分析急倾斜俯伪斜采场矿压规律模拟分析 ............................................................................. 30 3.3.1 FLAC3D 软件介绍 .................................................................................................. 30 3.3.2 数值计算参数 ......................................................................................................... 31 3.3.3 数值模型的建立 ..................................................................................................... 31 3.3.4 模拟结果分析 ......................................................................................................... 32 3.4 ““平行四边形平行四边形””采场顶板破断规律模拟分析采场顶板破断规律模拟分析 .................................................................. 44 万方数据 重庆大学硕士学位论文 VI 3.4.1 模型建立 ................................................................................................................. 45 3.4.2 均布荷载下的顶板破断演化规律 ......................................................................... 46 3.4.3 非均布荷载下顶板破断演化规律 ......................................................................... 47 3.5 本章小结本章小结 ............................................................................................................................ 48 4 急倾斜俯伪斜采场矿压规律实测研究急倾斜俯伪斜采场矿压规律实测研究 ................................................................. 51 4.1 引言引言 .................................................................................................................................... 51 4.2 矿山压力观测方案矿山压力观测方案 ............................................................................................................ 51 4.2.1 矿山压力监测区布置 ............................................................................................. 51 4.2.2 矿压观测系统 ......................................................................................................... 51 4.2.3 矿压观测过程 ......................................................................................................... 52 4.3 采场矿山压力显现规律现场实测研究采场矿山压力显现规律现场实测研究 ............................................................................ 53 4.3.1 采场顶板来压判断 ................................................................................................. 53 4.3.2 顶板垮落及来压特征 ............................................................................................. 55 4.3.3 顶板压力综合分析 ................................................................................................. 57 4.4 本章小结本章小结 ............................................................................................................................ 59 5 急倾斜俯伪斜综采工作面支架适应性急倾斜俯伪斜综采工作面支架适应性分析分析....................................................... 61 5.1 引言引言 .................................................................................................................................... 61 5.2 工作面支架适应性分析工作面支架适应性分析 .................................................................................................... 61 5.2.1 支架适应性分析 ..................................................................................................... 61 5.2.2 支护参数合理性分析 ............................................................................................. 63 5.3 支架运行特性评价支架运行特性评价 ............................................................................................................ 66 5.4 本章小结本章小结 ............................................................................................................................ 69 6 结论及展望结论及展望 ............................................................................................................................ 71 6.1 结论结论 .................................................................................................................................... 71 6.2 展望展望 .................................................................................................................................... 73 致致 谢谢 ...................................................................................................................................... 75 参考文献参考文献 ...................................................................................................................................... 77 附附 录录 ...................................................................................................................................... 81 A. 作者在攻读学位期间发表的学术论文作者在攻读学位期间发表的学术论文 .............................................................................. 81 B. 作者在攻读学位期间参与的科研项目作者在攻读学位期间参与的科研项目 .............................................................................. 81 万方数据 1 绪 论 1 1 绪 论 1.1 研究背景及意义 急倾斜煤层是指赋存倾角大于 45的煤层, 我国急倾斜煤层的储量约占煤炭 总储量的 17,其年产量却仅占全国煤炭总产量的 3[1,2]。据统计,我国 626 处 国有重点煤矿和地方煤矿中,开采急倾斜煤层的矿井有 103 处,占 16.5[3]。近 年来随着矿井开采深度和强度的增加,一些地区优质煤炭资源面临枯竭的境况, 为保证矿井的可持续发展,满足全国煤炭总需求,越来越多的矿区开始转入到急 倾斜煤层的开采,甚至是急倾斜薄煤层的开采,如山东兖州、河北邢台和开滦、 安徽淮南、江苏徐州及贵州、四川、重庆、云南、新疆、甘肃、宁夏等省(区) 的矿区[4,5]。相比于近水平及缓倾斜煤层而言,急倾斜煤层由于煤层赋存倾角大, 顶板受力具有明显的非对称性[6-9], 导致其顶板破坏特征有别于近水平及缓倾斜煤 层。急倾斜采场顶板破断特征将影响到工作面矿压显现[10,11]、工作面设备防滑防 倒[12-14]及巷道支护设计[15,16]等工程问题,因此研究急倾斜采场工作面顶板破断特 征及矿压规律对急倾斜煤层开采具有重要的理论指导和工程实践意义。而急倾斜 煤层工作面不沿真倾斜方向布置而沿伪倾斜方向布置时,采场不再是矩形采场, 而是近似于平行四边形采场,采场顶板破断规律、工作面矿压规律也不同于以往 的急倾斜采场。因此研究急倾斜俯伪斜采场顶板破断及工作面矿压规律是很有必 要的。 1.2 国内外研究现状 1.2.1 采场矿山压力理论国内外的研究现状 为揭示矿山开采过程中采场上覆岩层的运动规律与破断机理,国内外采矿专 家、学者在总结大量的现场经验并以力学分析为理论基础,提出了许多矿山压力 假说[10,17],这些理论在一定程度上解释了矿山压力现象的内在联系推断和科学性 的总结概括。 ①自然平衡拱假说 俄国学者 M.M.普罗托吉亚阔诺夫在观察总结煤矿巷道顶板破坏的基础上提 出了自然平衡拱假说理论。该假说认为巷道掘进以后,巷道顶板部分上覆岩层 将会发生一定程度的松动,并垮落成为类似半圆拱的结构。由于自然平衡拱假说 没有从岩石破坏和应力重分布的角度解释其形成的机理,也没有深入研究围岩中 应力分布和稳定的条件,因此该假说无法确定扩展后的平衡拱位置。在平衡拱假 说的发展过程中,曾有很多人尝试着用该假说来解释采煤工作面推进过程中周围 万方数据 重庆大学硕士学位论文 2 岩层中的应力和支架上显现的压力并建立了相应的力学模型,但是在后续的研究 中发现,利用平衡拱假说可以解释采煤工作面初次来压期间煤壁前方支承压力及 采煤工作面支架上显现的压力随采煤工作面推进而增加的现象,但是无法解释采 煤工作面周期来压的矿压显现规律。因此,自然平衡拱假说无法解决采煤工作面 产生的矿山压力问题。 ②压力拱假说 德国学者 W.Hack 和 G.Gillitzer 于 1928 年提出了压力拱假说,该假说在 20 世纪 50 年代前后得到了很多学者的拥护和支持,其中影响比较大的是前苏联学 者 Φ.许普鲁特的假说模型, 他认为, 采场是在一个“前脚在煤壁, 后脚在采空区” 拱结构的保护之下。该假说的基本观点是(1)支承压力的形成是由于压力拱 切断了拱内和拱外岩石之间的力学联系,压力拱形成后一方面承担了其上部岩石 的重量,另一方面会将其作用力分担到四周拱脚部位。(2)在整个开采过程中, 采煤工作面支架仅承担压力拱内部受开采扰动的岩体重量,使得支架只在一定的 荷载条件下运行,因此支架在工作过程中本身的承载能力和力学运行特性无法决 定工作