(1. State Key Laboratory of Gas Disaster Detecting，Preventing and Emergency Controlling，Chongqing 400037，China；2. State Key Laboratory of Coal Mine Disaster Dynamics and Control，Chongqing University，Chongqing 400044，China；3. School of Resources and Safety Engineering，Chongqing University，Chongqing 400044，China；4. Chongqing Research Institute，China Coal Technology and Engineering Group，Chongqing 400037，China)
Abstract：In order to investigate the motion instability of the hard roof in incline thick coal seam，a numerical model for mining covered rock in such seam was established using PFC2D discrete element particle flow analysis software. A hydraulic weakening program was designed to address the issue of large area hanging arch in the hard roof. The study analyzed the influence of different fracturing parameters on the effectiveness of hydraulic weakening and proposed an optimization method for selecting hydraulic weakening. parameters. The study revealed that the hard roof of incline thick coal seam undergoes a “Dam-shaped block” breakdown under initial weighting，and the vertical stress of overlying strata above the goaf exhibits asymmetric characteristics，resulting in stepped collapse in longitudinal direction as the working face advances；Four hydraulic weakening schemes with different fracturing angles and three different fracturing heights were proposed for large area hanging arch of incline thick coal seam. The results showed that the weakening scheme with a fracturing angle of “right angle” and a fracturing height of half of the thickness of the basic roof achieved the expected weakening effect. The weakening scheme reduced the hydraulic weakening influence area of the hard roof，resulting in an overall decrease in ground pressure strength，with a reduction of about 42% in peak pressure and 52% in weighting step distance；Considering the construction difficulty and cost，the hydraulic weakening parameters of the hard roof of incline thick coal seam was optimized. Based on the relationship between weakened degree and fracturing angle and height，a preferred method of non-fully oriented hydraulic weakening parameters of the hard roof of incline thick coal seam was proposed. An industrial test was conducted in the 1E201 working face，yielding a significant weakening effect on the roof.
梁运培1，2，3，李其罡2，3，黄旭超1，3，4，武兆鹏2，3，陈 亮1，3，4. 基于颗粒流的倾斜厚煤层坚硬顶板运动失稳规律及水力弱化参数研究[J]. 岩石力学与工程学报, 2024, 43(S1): 3428-3438.
LIANG Yunpei1，2，3，LI Qigang2，3，HUANG Xuchao1，3，4，WU Zhaopeng2，3，CHEN Liang1，3，4. Study on movement instability law and hydraulic weakening parameters of hard roof in inclined thick coal seam based on particle flow. , 2024, 43(S1): 3428-3438.
[1] 李姗姗，袁 亮. 煤炭工业全生命周期碳排放核算与影响因素[J]. 煤炭学报，2023，48(7)：2 925–2 935.(LI Shanshan，YUAN Liang. Carbon emission accounting and influencing factors for whole life cycle of coal industry[J]. Journal of China Coal Society，2023，48(7)：2 925–2 935.(in Chinese))
[2] 王海洋，于 斌，夏彬伟，等. 复合坚硬顶板水压裂缝扩展过程研究[J]. 中国安全科学学报，2017，27(4)：98–103.(WANG Haiyang，YU Bin，XIA Binwei，et al. Study on propagation of hydraulic fracture in combined hard roof[J]. China Safety Science Journal，2017，27(4)：98–103.(in Chinese))
[3] 王海洋，赵树磊，刘佳亮，等. 垂直贯穿裂缝对坚硬顶板失稳破断的影响特征[J]. 中国安全科学学报，2020，30(1)：66–72.(WANG Haiyang，ZHAO Shulei，LIU Jialiang，et al. Study on influencing characteristics of vertical penetrating crack on instability and breaking of hard roof[J]. China Safety Science Journal，2020，30(1)：66–72.(in Chinese))
[4] 钱鸣高，许家林. 煤炭开采与岩层运动[J]. 煤炭学报，2019，44(4)：973–984.(QIAN Minggao，XU Jialin. Behaviors of strata movement in coal mining[J]. Journal of China Coal Society，2019，44(4)：973–984.(in Chinese))
[5] 伍永平，解盘石，任世广. 大倾角煤层开采围岩空间非对称结构特征分析[J]. 煤炭学报，2010，35(2)：182–184.(WU Yongping，XIE Panshi，REN Shiguang. Analysis of asymmetric structure around coal face of steeply dipping seam mining[J]. Journal of China Coal Society，2010，35(2)：182–184.(in Chinese))
[6] LUO S，WANG T，WU Y，et al. Internal mechanism of asymmetric deformation and failure characteristics of the roof for longwall mining of a steeply dipping coal seam[J]. Archives of Mining Sciences，2021，(1)：66.
[7] 王金安，张基伟，高小明，等. 大倾角厚煤层长壁综放开采基本顶破断模式及演化过程(Ⅰ)—初次破断[J]. 煤炭学报，2015，40(6)：1 353–1 360.(WANG Jin?an，ZHANG Jiwei，GAO Xiaoming，et al. Fracture mode and evolution of main roof stratum above longwall fully mechanized top coal caving in steeply inclined thick coal seam(I)—initial fracture[J]. Journal of China Coal Society，2015，40(6)：1 353–1 360.(in Chinese))
[8] 王金安，张基伟，高小明，等. 大倾角厚煤层长壁综放开采基本顶破断模式及演化过程(Ⅱ)—周期破断[J]. 煤炭学报，2015，40(8)：1 737–1 745.(WANG Jin?an，ZHANG Jiwei，GAO Xiaoming，et al. Fracture mode and evolution of main roof stratum above longwall fully mechanized top coal caving in steeply inclined thick coal seam(Ⅱ)—Periodic breaking[J]. Journal of China Coal Society，2015，40(8)：1 737–1 745.(in Chinese))
[9] 解盘石，屈利利，伍永平，等. 大倾角近距离煤层群长壁采场顶板破断机制[J]. 煤炭科学技术，2022，50(2)：65–74.(XIE Panshi，QU Lili，WU Yongping，et al. Roof breaking mechanism of longwall stope with steeply dipping contagious coal seam group[J]. Coal Science and Technology，2022，50(2)：65–74.(in Chinese))
[10] 曹晋荣，窦林名，何 江，等. 急倾斜特厚煤层工作面非对称冲击矿压机制[J]. 采矿与安全工程学报，2023，40(2)：334–345.(CAO Jinrong，DOU Linming，HE Jiang，et al. Mechanism of asymmetric coal bursts on the working face in steeply inclined and extra-thick coal seam[J]. Journal of Mining and Safety Engineering，2023，40(2)：334–345.(in Chinese))
[11] 李 楠. 综采工作面厚硬砂岩顶板深孔爆破预裂卸压技术与应用[J]. 煤炭技术，2022，41(7)：143–147.(LI Nan. Hole blasting presplitting pressure relief technology and its application in thick hard sandstone roof of fully mechanized mining face[J]. Coal Technology，2022，41(7)：143–147.(in Chinese))
[12] 单鹏飞，来兴平，崔 峰，等. 急斜煤层采空区顶板弱化方案优化及效果评价[J]. 西安科技大学学报，2019，39(3)：381–387.(SHAN Pengfei，LAI Xingping，CUI Feng，et al. Scheme optimization and its effect evaluation of void roof weakening in mining steeply inclined coal seams[J]. Journal of Xi?an University of Science and Technology，2019，39(3)：381–387.(in Chinese))
[13] 武尚俭. 静态破碎剂弱化致裂煤层坚硬顶板实验研究[硕士学位论文][D]. 徐州：中国矿业大学，2019.(WU Shangjian. Experimental study on cracked coal seam hard roof by static cracking agents[M. S. Thesis][D]；Xuzhou：China University of Mining and Technology，2019.(in Chinese))
[14] 苏 波. 水力压裂技术在煤矿坚硬难垮顶板中的应用[J]. 煤炭工程，2019，51(4)：54–57.(SU Bo. Application of hydraulic fracturing technology in hard and stable roof in coal mine[J]. Coal Engineering，2019，51(4)：54–57.(in Chinese))
[15] 牛同会. 分段水力压裂弱化采场坚硬顶板围岩控制技术研究[J]. 煤炭科学技术，2022，50(8)：50–59.(NIU Tonghui. Study on surrounding rock control technology for weakened hard roof of stope by staged hydraulic fracturing[J]. Coal Science and Technology，2022，50(8)：50–59.(in Chinese))
[16] 赵善坤. 深孔顶板预裂爆破与定向水压致裂防冲适用性对比分析[J]. 采矿与安全工程学报，2021，38(4)：706–719.(ZHAO Shankun. A comparative analysis of deep hole roof pre-blasting and directional hydraulic fracture for rockburst control[J]. Journal of Mining and Safety Engineering，2021，38(4)：706–719.(in Chinese))
[17] 段宏飞，杨 强. 水力压裂控制坚硬顶板室内试验及现场测试[J]. 煤矿安全，2019，50(7)：26–30.(DUAN Hongfei，YANG Qiang. Lab experiment and field test of hydraulic fracturing in controlling hard roof[J]. Safety in Coal Mines，2019，50(7)：26–30.(in Chinese))
[18] 王玉军，李晓旭，冀瑞锋，等. 综放工作面强动压巷道围岩综合控制技术研究与应用[J]. 煤炭工程，2023，55(8)：51–57.(WANG Yujun，LI Xiaoxu，JI Ruifeng，et al. Research and application of comprehensive surrounding rock control technology for strong dynamic pressure roadway in longwall top-coal caving face[J]. Coal Engineering，2023，55(8)：51–57.(in Chinese))
[19] 司瑞江，李飞鹏，赵璐璐，等. 区段大煤柱水力压裂切顶护巷技术研究[J]. 煤炭科学技术，2020，48(7)：282–287.(SI Ruijiang，LI Feipeng，ZHAO Lulu，et al. Research on hydraulic fracturing roof cutting and roadway protection technology with wide sublevel coal pillar[J]. Coal Science and Technology，2020，48(7)：282–287.(in Chinese))
[20] 徐雪战. 低透气煤层超高压水力割缝与水力压裂联合增透技术[J]. 煤炭科学技术，2020，48(7)：311–317.(XU Xuezhan. Combined permeability enhancement technology of ultra-high pressure hydraulic slot and hydraulic fracturing in low permeability coal seam[J]. Coal Science and Technology，2020，48(7)：311–317.(in Chinese))
[21] 陈冬冬，孙四清，张 俭，等. 井下定向长钻孔水力压裂煤层增透技术体系与工程实践[J]. 煤炭科学技术，2020，48(10)：84–89.(CHEN Dongdong，SUN Siqing，ZHANG Jian，et al. Technical system and engineering practice of coal seam permeability improvement through underground directional long borehole hydraulic fracturing[J]. Coal Science and Technology，2020，48(10)：84–89.(in Chinese))
[22] 袁国涛，张明伟，王 杰，等. 采动覆岩微震分区演化特征的数值模拟研究[J]. 煤炭科学技术，2023，51(8)：36–46.(YUAN Guotao，ZHANG Mingwei，WANG Jie，et al. Numerical simulation study on sub-regional evolution of microseismic characteristics of mining overburden rock[J]. Coal Science and Technology，2023，51(8)：36–46.(in Chinese))
[23] 黄炳香，赵兴龙，陈树亮，等. 坚硬顶板水压致裂控制理论与成套技术[J]. 岩石力学与工程学报，2017，36(12)：2 954–2 970. (HUANG Bingxiang，ZHAO Xinglong，CHEN Shuliang，et al. Theory and technology of controlling hard roof with hydraulic fracturing in underground mining[J]. Chinese Journal of Rock Mechanics and Engineering，2017，36(12)：2 954–2 970.(in Chinese))
[24] 王楠楠，高 霞，张吉哲，等. 基于平行黏结模型的含瓦斯水合物煤体宏细观力学性质研究[J/OL]. 煤炭学报，DOI：10.13225/ j.cnki.jccs.2023.0580.(WANG Nannan，GAO Xia，ZHANG Jizhe，et al. Macro-micro mechanical behavior research on gas hydrate bearing coal based on parallel bonding model[J/OL]. Journal of China Coal Society，DOI：10.13225/j.cnki.jccs.2023.0580.(in Chinese))
[25] 陈鹏宇，孔 莹，余宏明. 岩石单轴压缩PFC2D模型细观参数标定研究[J]. 地下空间与工程学报，2018，14(5)：1 240–1 249.(CHEN Pengyu，KONG Ying，YU Hongming. Research on the calibration method of micro parameters of a uniaxial compression PFC2D model for rock[J]. Chinese Journal of Underground Space and Engineering，2018，14(5)：1 240–1 249.(in Chinese))
[26] 程 毅，丁耀胜，李松龄，等. 离散元光滑节理模型中颗粒“非正常重叠”的机制研究[J/OL]. 工程力学，DOI：http：//kns.cnki.net/ kcms/detail/11.2595.O3.20230325.1855.002.html. (CHENG Yi，DING Yaosheng，LI Songling，et al. Study on the mechanism of “abnormal overlap” of particles in discrete element smooth-joint model[J/OL]. Engineering Mechanics，DOI：http：//kns.cnki.net/kcms/detail/ 11.2595.O3.20230325.1855.002.html. (in Chinese))
[27] 刘洪伟，李君利. 坚硬顶板弱化技术综述[J]. 煤炭技术，2009，28(2)：50–51.(LIU Hongwei，LI Junli. Integrated description of hard roof weakening technology[J]. Coal Technology，2009，28(2)：50–51.(in Chinese))
[28] 温颖远，郭志刚，曹安业，等. 基于微震数据评价的顶板深孔爆破卸压效果分析[J]. 煤炭科学技术，2020，48(6)：57–63.(WEN Yingyuan，GUO Zhigang，CAO Anye，et al. Analysis of pressure relief effect of roof deep hole blasting based on microseismical data evaluation[J]. Coal Science and Technology，2020，48(6)：57–63.(in Chinese))
[29] 左建平，孙运江，刘文岗，等. 浅埋大采高工作面顶板初次断裂爆破机制与力学分析[J]. 煤炭学报，2016，41(9)：2 165–2 172.(ZUO Jianping，SUN Yunjiang，LIU Wengang，et al. Mechanical analysis and blasting mechanism of main roof initial fracturing in shallow depth mining face with large cutting height[J]. Journal of China Coal Society，2016，41(9)：2 165–2 172.(in Chinese))
[30] 贾光明. 金川煤矿综放煤层分区弱化注水防冲技术研究[硕士学位论文][D]. 西安：西安科技大学，2020.(JIA Guangming. Study on the Technology of weakening Water injection to prevent erosion in Subarea of fully mechanized caving coal seam in Jinchuan coal mine[M. S. Thesis][D]. Xi?an：Xi?an University of Science and Technology，2020.(in Chinese))
[31] 林志斌，李亚超，吴疆宇，等. 水力压裂对末采矿压显现规律的影响研究[J]. 采矿与安全工程学报，2023，40(4)：714–721.(LIN Zhibin，LI Yachao，WU Jiangyu，et al. Influence of hydraulic fracturing on the behavior of mine pressure at the end of mining[J]. Journal of Mining and Safety Engineering，2023，40(4)：714–721.(in Chinese))
2024, Vol. 43 
