急倾斜煤层残留煤柱下综放工作面动力灾害防治研究.pdf

论文题目急倾斜煤层残留煤柱下综放工作面动力灾害防治研究 专业采矿工程 硕 士 生闫瑞兵（签名）闫瑞兵） 指导教师范公勤（签名）范公勤） 陈建强（签名）陈建强） 摘要 新疆是国家规划建设的第十四个高起点、高标准、高效益的亿吨级大型煤炭基地， 也是“一带一路”经济带规划建设的主体能源基地。由神华新疆能源有限责任公司主采的 乌鲁木齐矿区急倾斜复杂难采特厚煤层占世界急倾斜煤层储量的 30。煤炭资源赋存环 境复杂4587，安全开采难度极大，动力灾害频发。 碱沟煤矿 B3-6 煤层属急倾斜特厚煤层87，采用水平分段综采放顶煤回采方法回 收顶煤，段高 24m。495 水平 B3-6 回采工作面通过上覆结构尺寸为长宽高 120m50m108m的残留煤柱。工作面经过煤柱时在开采扰动作用下形成复杂的空间结 构工作面夹持于顶、岩柱及残留煤柱之间，围岩在静-动载荷作用下极易诱发动力灾 害。通过理论分析认为残留煤柱诱发动力灾害主要有以下三点a.煤柱夹持于顶底板之 间造成水平应力集中从而引起剪应力大大增加，使煤柱易发生剪切破坏；b.煤柱的存在 使得 B3-6 煤层与 B1-2 煤层中间岩柱内部应力增大，煤柱内部应力与岩柱自重 G、水平 应力 q0及煤柱段高 h0呈正相关；c.在走向方向煤柱受工作面采动影响，煤柱内部集中应 力与工作面超前支承应力互相叠加，使得在残留煤柱危险范围内，工作面前方应力大大 增加。采用数值模拟分析煤柱未受采动和采动影响下煤柱内部应力变化情况，得出在 残留煤柱前方 60120m 处、060m 处，-600m 处工作面支架顶部应力具有明显的分区 特性，应力平稳区60120m 处、应力过渡区060m 处、应力叠加区-600m，在应力 过渡区与应力叠加区应力集中明显，受采动影响极易诱发动力灾害。通过在石门内布置 扇形注水、爆破孔；495B3 巷布置高阶段超前爆破孔；正常的超前预裂注水、爆破孔； 岩柱预裂注水、爆破孔及顶板深孔预裂爆破孔。对煤柱危险区域充分卸压，实现工作面 安全、高效通过残留煤柱危险区域。 本研究对于实现急倾斜特厚煤层工作面过残留煤柱安全高效开采及岩柱稳定性控制 具有指导意义。 关关 键键 词词急倾斜特厚煤层、残留煤柱、动力灾害、爆破卸压 研究类型研究类型应用研究 Thesis title Study on dynamic disaster prevention under fully-mechanized mining face of the residual pillar of steeply inclined coal seam SpecialtyMining Engineering NameYan Ruibing（（Signature））YanRuibing InstructorFan Gongqin（（Signature））FanGongqin Chen Jianqiang（（Signature）） ChenJianqiang ABSTRACT Sinkiang is the 14th national planned and constructed 100-million-ton large coal base of a high starting point, high standard and high benefit. It is also the main energy base of “the Belt and Road Initiatives“ economic zone planning and construction. The steeply inclined extremely-thick coal seam of the Urumqi mining managed by Shen-hua Xinjiang Energy CO.,LTD. accounts for 30 of the world’s deeply inclined coal resources. The existing condition of the coal resources is quite complex 4587, safe mining is extremely hard, and dynamic disasters occur frequently. The B3-6 coal seam of Jiangou coal mine belongs to the steeply inclined extremely-thick coal seam 87, and the horizontal sublevel caving mining is used. The 495 horizontal B3-6 working face works through the residual pillar of lengthwidthheight 120m50m108m. The working face s a complex spatial structure under the action of mining the working face clamps between roof, floor and the overlying coal pillar and the surrounding rock induces dynamic disasters easily under the action of static and dynamic load. Through theoretical analysis, the three main points for the residual-pillar-induced dynamic disasters are as follows. A. the pillar clamps between the roof and floor and makes the horizontal stress concentrated and thus leads to great shear stress increase, making the coal pillar prone to shear failure. B. the residual coal pillar makes the internal stress of the rock pillar between B3-6 coal seam and B1-2 coal seams increase, and the internal stress of coal pillar positively correlates with rock pillars gravity G, horizontal stress q0and high coal pillar section h0. C. affected by the mining of the working face, the internal concentration stress of the coal pillar and the abutment stress of the working face overlaps, leading to great stress increase in front of the working face at the dangerous scope of the residual coal pillar. By analyzing the internal stress difference of coal pillars when not affected by the mining and affected by the mining using FLAC3D, it can be concluded that the top stress of the working face varies obviously at 60120m distance to the pillar, 060m distance to the pillar and -600m distance to the pillar and they are separately the smooth stress zone 60120m, the stress transition zone 060m and the stress superposition zone -600m. The stress concentrates significantly at stress transition zone and stress superposition zone and dynamic disasters are easily induced. The working face’s safe and efficient across through of the dangerous zone of the residual coal pillar can be achieved by arranging fan-shaped blasting hole in the cross-hole, arranging high phase advance blasting hole in 495 B3 roadway, arranging normal pre-splitting water injection and blast holes in advance and arranging rock column precracking water injection and blasting holes and top deep hole pre-split blasting holes to sufficiently release pressure of the dangerous zone of the coal pillar. This study has guiding significance for safe and efficient mining through overlying residual pillar of steeply inclined extremely-thick coal seam working face and rock pillars stability control. Keywords Steeply inclined extremely-thick coal seam, overlying residual pillar, dynamic disasters, blasting pressure relief ThesisApplication research III 目录 1 绪论..........................................................................................................................................1 1.1 论文选题背景和意义...................................................................................................1 1.1.1 选题背景............................................................................................................1 1.1.2 选题意义............................................................................................................2 1.2 国内外的研究现状.......................................................................................................2 1.2.1 动力灾害发生机理研究现状............................................................................2 1.2.2 煤柱型动力灾害研究现状................................................................................5 1.2.3 煤岩体致裂卸压研究现状................................................................................6 1.3 本课题拟研究的主要内容...........................................................................................6 1.4 课题拟采取的研究方案及技术路线...........................................................................7 1.4.1 研究方案............................................................................................................7 1.4.2 技术路线............................................................................................................7 2 矿井地质及灾害特征..............................................................................................................8 2.1 矿井地质特征...............................................................................................................8 2.1.1 煤层赋存特征....................................................................................................8 2.1.2 煤层顶底板岩性................................................................................................9 2.1.3 工作面概况......................................................................................................10 2.1.4 生产技术条件.................................................................................................10 2.2 急倾斜煤层残留高阶段煤柱结构勘查.....................................................................11 2.3 急倾斜煤层残留煤柱结构动力失稳多源灾害分析.................................................12 2.3.1 矿压显现..........................................................................................................12 2.3.2 有害气体涌出..................................................................................................13 2.3.3 自然发火..........................................................................................................13 2.3.4 采空区积水突出..............................................................................................13 2.3.5 地表变形与破坏..............................................................................................14 2.4 相似地质条件冲击地压历史事件.............................................................................14 2.4.1“2.27”事件......................................................................................................14 2.4.2“7.2”事件........................................................................................................15 2.4.3“3.13”事件......................................................................................................15 2.4.4“11.24”事件....................................................................................................15 2.5 本章小结.....................................................................................................................16 3 急倾斜煤层残留煤柱失稳灾变机理分析............................................................................17 IV 3.1 地质影响因素.............................................................................................................17 3.2 开采技术影响因素.....................................................................................................18 3.3 残留煤柱结构影响因素.............................................................................................18 3.3.1 倾向方向煤柱受力分析..................................................................................19 3.3.2 走向方向煤柱受力分析..................................................................................22 3.4 本章小结.....................................................................................................................24 4 急倾斜煤层残留煤柱失稳应力分析....................................................................................25 4.1 模型构建.....................................................................................................................25 4.2 力学参数确定.............................................................................................................26 4.3 应力分析.....................................................................................................................26 4.3.1 煤体初始应力..................................................................................................26 4.3.2 直接顶初始应力..............................................................................................27 4.3.3 岩柱初始应力..................................................................................................27 4.3.4 岩柱应力对比..................................................................................................28 4.3.5 煤体应力对比..................................................................................................29 4.3.6 开挖扰动应力分析..........................................................................................30 4.4 本章小结....................................................................................................................31 5 急倾斜煤层残留煤柱动力灾害防治....................................................................................32 5.1 高应力场分布范围.....................................................................................................32 5.2 煤柱卸压工程.............................................................................................................33 5.2.1 东三采区590m 水平......................................................................................33 5.2.2 东三采区564m 水平......................................................................................34 5.2.3 东三采区541m 水平......................................................................................36 5.2.4 东三采区518m 水平......................................................................................37 5.3 其他区域卸压措施.....................................................................................................39 5.3.1 安宁渠煤矿边界保护煤柱内高阶段超前预裂爆破......................................39 5.3.2 本分层超前注水、爆破预裂..........................................................................39 5.3.3 岩柱注水、爆破预裂......................................................................................40 5.3.4 顶板深孔爆破..................................................................................................40 5.4 本章小结.....................................................................................................................41 6 急倾斜煤层残留煤柱综合治理效果评价............................................................................42 6.1 钻孔窥视检测.............................................................................................................42 6.1.1 钻孔窥视简介..................................................................................................42 6.1.2 探测结果..........................................................................................................43 V 6.2 微震监测数据分析.....................................................................................................44 6.2.1 微震监测系统简介..........................................................................................44 6.2.2 微震监测系统井下布置..................................................................................45 6.2.3 探测结果..........................................................................................................45 6.3 地音监测.....................................................................................................................46 6.3.1 监测系统工作原理..........................................................................................46 6.3.2 地音监测数据预警原则..................................................................................47 6.3.3 地音监测系统井下布置..................................................................................47 6.3.4 地音监测结果..................................................................................................48 6.4 工作面支架压力监测及矿压显现情况.....................................................................49 6.5 PASAT-M 便携式微震探测系统监测........................................................................51 6.5.1PASAT-M 便携式微震探测系统简介..............................................................51 6.5.2 探测结果..........................................................................................................51 6.6 本章小结.....................................................................................................................53 7 结论........................................................................................................................................54 致谢...........................................................................................................................................56 参考文献...................................................................................................................................57 1 绪论 1 1 绪论 1.1 论文选题背景和意义 1.1.1 选题背景 中国属煤炭资源富集国，从 80 年代起，煤炭对我国国民经济的发展具有主导作用。 它不仅是主要的消费能源，还是主要的化工原料，是我国经济腾飞的主要动力[1]。随着 我国西部大开发战略的推进，矿产资源开发的关键在向西部转移，开发煤炭资源已成为 西部地区区域经济发展的中坚力量， 占全国煤炭总储量的 1520[2]， 尤其是新疆地区 的急倾斜煤层占有一定的比例， 因此加强对急倾斜煤层安全高效开采研究是西部煤炭开 采的重大课题[3-10]。 煤炭在我国国民经济发展中占有重要地位，不仅是主要能源，同时又是主要化工原 料，在国民经济建设中具有重要地位。随着我国西部大开发战略的实施，我国矿产资源 开采重点西移，煤炭资源开采已成为西部地区区域经济发展的重要支柱，水平分段综放 开采是急倾斜特厚煤层实现安全高效开采的有效方法，其典型特征为工作面回采之后 形成的采空区含地下水、破碎煤岩和瓦斯等气体位于下分段工作面之上[11-12]。随着煤 层开拓水平深部延伸，综放工作面破碎煤岩易形成多分段结构空间，加之历史原因浅 部小煤窑众多及残留煤柱保护煤柱， 综放工作面极易受到因结构失稳或残留煤柱失稳 诱发的冲击作用[13]。因此，基于煤岩体局部变形失稳理论，揭示急倾斜特厚煤层残留煤 柱失稳机理，对指导现场安全高效开采具有重要意义。 以碱沟煤矿495 水平东翼回采区域经过安宁渠煤矿边界保护煤柱和东三石门保护 煤柱为例。安宁渠煤矿井田范围东、西翼开采不均衡，根据钻探资料推算，其东翼已开 采至520 水平，其西翼开采至564 水平。地表已大面积垮落，但其东西边界保护煤柱 仍相对完整。尤其是其东边界保护煤柱与东三采区石门保护煤柱相连，形成较大面积的 煤柱结构对东翼495 水平工作面回采的动力灾害显现影响显著，但目前对碱沟煤矿围 岩活动规律及异常区域应力演化与灾变规律还不清楚， 动力显现是碱沟煤矿目前所面临 的主要安全隐患，如何进行有效的进行应力异常监测及围岩灾变控制显得尤为重要。需 要有针对性的开展煤柱区域围岩活动及影响区应力演化监测及分析， 确定煤柱影响范围 及应力异常分布规律，评价工作面开采至该区域期间动力灾害危险程度，