Influence of coal seam thickness on pressure relief and energy releasemechanism of large-diameter drilling hole
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摘要:
煤层厚度变化是影响大直径钻孔卸压效果的重要因素之一。基于等效弹性模量原理建立了大直径钻孔卸压弹性力学模型，以某矿不同工作面为工程背景，研究了不同煤层厚度条件下大直径钻孔卸压煤体应力分布特征和能量释放规律，探讨了煤层厚度影响下大直径钻孔卸压释能机理。研究结果表明：当大直径钻孔卸压参数相同时，薄煤层中原岩应力、钻孔切向应力及其塑性区范围均大于厚煤层；大直径钻孔周边应力峰值随煤层厚度增加呈非线性减小趋势，当煤层厚度由1 m增加到9 m，应力峰值由23.2 MPa降低到20.2 MPa，降低12.9%；大直径钻孔卸压释能率随着煤层厚度增加呈减小趋势，当煤层厚度由1 m增加到9 m，大直径钻孔卸压释能率由68.7%降低到45.8%，即相同大直径钻孔卸压参数条件下薄煤层卸压效果更好；当大直径钻孔卸压参数相同时，钻孔切向应力随着煤层厚度增加而减小，导致煤体破碎区和塑性区范围以及存储弹性能释放量减小，即钻孔卸压释能率降低。某矿1208工作面和1203工作面煤层厚度分别为9.08、4.95 m，虽然两工作面采取了相同的大直径钻孔参数，但1208工作面巷道围岩变形破坏更为严重，对大直径卸压钻孔参数优化后，煤体平均钻屑量由2.48 kg/m下降到1.76 kg/m，表明随着煤层厚度增加，需采取减小钻孔间距、增大钻孔直径等措施来达到更好的卸压效果。
Abstract:The variation of coal seam thickness is one of the important factors affecting the pressure relief of large-diameter drilling hole. We have established an elastic model of pressure relief of large-diameter drilling hole based on the principle of equivalent elastic modulus. Taking two working faces of a mine as engineering background, we have studied key issues of large-diameter drilling hole regarding coal seam thickness, including the stress distribution characteristics and energy release laws, and the pressure relief and energy release mechanism. Several phenomena of engineering significance have been revealed by our research. Firstly, when the parameters of large-diameter drilling hole are the same, the stress of primary rock, tangential stress and plastic zone range of thin coal seam are greater than those of thick coal seam. Secondly, the peak stress around the large-diameter drilling hole decreases nonlinearly with the increase of coal seam thickness. When the coal seam thickness increases from 1 m to 9 m, the peak stress drops by 12.9%, from 23.2 MPa to 20.2 MPa. Likewise, the pressure relief and energy release rate also decreases with the increase of coal seam thickness. When the coal seam thickness increases from 1 m to 9 m, the pressure relief and energy release rate of large-diameter drilling hole decreases from 68.7% to 45.8%, indicating that better pressure relief effect can be achieved in thin coal seam. Moreover, when the parameters of large-diameter drilling hole are the same, the increase of coal seam thickness causes decrease of the tangential stress and thereby results in the decrease of the range of coal fragmentation zone and plastic zone, and the amount of the released elastic energy, which reduces the pressure relief energy release rate. The coal seam thicknesses of working faces 1208 and 1203 of a certain mine are 9.08 m and 4.95 m, respectively. Although the same set of large-diameter drilling hole parameters is adopted for these two working faces, the one with thicker coal seam suffers from more serious surrounding rock deformation and failure. By optimizing the parameters of large-diameter drilling hole based on our research, the average amount of drilling cuttings decreased from 2.48 kg/m to 1.76 kg/m. Therefore, we suggest that as the coal seam thickness increases, measures such as reducing drilling spacing and increasing drilling diameter should be considered in order to guarantee the expected pressure relief effect.
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图 1 不同煤层厚度等效弹性模量示意
Figure 1. Diagram of equivalent elastic modulus of different coal seam thicknesses
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图 3 不同煤层厚度钻孔周边切向应力大小
Figure 3. Tangential stress around drilling hole under different coal seam thicknesses
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图 5 不同煤层厚度钻孔周围塑性区分布
Figure 5. Distribution of plastic zones around drilling hole under different coal seam thicknesses
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图 6 不同煤层厚度下大直径钻孔周边垂直应力演化规律
Figure 6. Evolution law of surrounding stress of large-diameter drilling hole under different coal seam thicknesses
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图 7 不同厚度煤层进行大直径钻孔卸压后高能区分布
Figure 7. Distribution of high energy zone after pressure relief by larg-diameter drilling hole under different coal seam thicknesses
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图 8 大直径钻孔卸压前后煤体弹性能演化规律
Figure 8. Elastic energy evolution law of coal before and after pressure relief of large-diameter drilling hole
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图 9 大直径钻孔卸压释能率与煤层厚度关系
Figure 9. Relationship between pressure relief and energy release rate of large-diameter drilling hole and coal seam thickness
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图 10 不同煤层厚度大直径钻孔卸压释能机理
Figure 10. Pressure relief and energy release mechanism of large-diameter drilling hole under different coal seam thicknesses
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图 12 1203与1208工作面巷道变形情况
Figure 12. Roadway deformation situation of working face No.1203 and No.1208
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图 13 不同钻孔间距下煤体垂直应力分布情况
Figure 13. Vertical stress distribution of coal mass under different drilling hole spacings
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图 14 不同钻孔直径下煤体垂直应力分布情况
Figure 14. Vertical stress distribution of coal mass under different drilling hole diameters
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图 15 大直径钻孔参数优化前后煤体钻屑量演化规律
Figure 15. Evolution law of coal cuttings before and after parameter optimization of large-diameter drilling hole
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图 16 巷道围岩破坏分区及锚固支护示意
Figure 16. Diagram of roadway surrounding rock failure zone and anchoring support
表 1 煤层及顶底板岩层物理力学参数
Table 1 Physical and mechanical parameters of coal, roof and floor Strata
岩性 弹性模量/GPa 泊松比 单轴抗压强度/MPa 内摩擦角/（°） 中细砂岩 7.20 0.20 20 36 2-2煤 2.40 0.20 23 31 砂质泥岩 13.80 0.15 30 36 
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表 2 大直径钻孔卸压释能率
Table 2 Pressure relief and energy release rate of large-diameter drilling hole
煤层
厚度/m能量密度/( MJ·m−3) 大直径钻孔
卸压释能率/%大直径钻孔
卸压后煤体大直径钻孔
卸压前煤体1 1.651 1 2.785 4 68.7 3 1.997 2 3.227 0 61.6 5 2.922 6 4.448 2 52.2 7 3.224 2 4.816 8 49.4 9 3.348 3 4.972 2 48.5
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[1] 谢和平,高 峰,鞠 杨. 深部岩体力学研究与探索[J]. 岩石力学与工程学报,2015,34(11):2161−2178. XIE Heping,GAO Feng,JU Yang. Research and development of rock mechanics in deep ground engineering[J]. Chinese Journal of Rock Mechanics and Engineering,2015,34(11):2161−2178.
[2] 谭云亮,王子辉,刘学生,等. 采动诱冲动能估算及冲击危险性评价[J]. 煤炭学报,2021,46(1):123−131. TAN Yunliang,WANG Zihui,LIU Xuesheng,et al. Estimation of dynamic energy induced by coal mining and evaluation of burst risk[J]. Journal of China Coal Society,2021,46(1):123−131.
[3] 蓝 航,齐庆新,潘俊锋,等. 我国煤矿冲击地压特点及防治技术分析[J]. 煤炭科学技术,2011,39(1):11−15,36. LAN Hang,QI Qingxin,PAN Junfeng,et al. Analysis on features as well as prevention and control technology of mine strata pressure bumping in China[J]. Coal Science and Technology,2011,39(1):11−15,36.
[4] 谭云亮,郭伟耀,辛恒奇,等. 煤矿深部开采冲击地压监测解危关键技术研究[J]. 煤炭学报,2019,44(1):160−172. TAN Yunliang,GUO Weiyao,XIN Hengqi,et al. Key technology of rock burst monitoring and control in deep coal mining[J]. Journal of China Coal Society,2019,44(1):160−172.
[5] 姜耀东,潘一山,姜福兴,等. 我国煤炭开采中的冲击地压机理和防治[J]. 煤炭学报,2014,39(2):205−213. JIANG Yaodong,PAN Yishan,JIANG Fuxing,et al. State of the art review on mechanism and prevention of coal bumps in China[J]. Journal of China Coal Society,2014,39(2):205−213.
[6] 窦林名,田鑫元,曹安业,等. 我国煤矿冲击地压防治现状与难题[J]. 煤炭学报,2022,47(1):152−171. DOU Linming,TIAN Xinyuan,CAO Anye,et al. Present situation and problems of coal mine rock burst prevention and control in China[J]. Journal of China Coal Society,2022,47(1):152−171.
[7] 李金奎,熊振华,刘东生,等. 钻孔卸压防治巷道冲击地压的数值模拟[J]. 西安科技大学学报,2009,29(4):424−426,432. doi: 10.3969/j.issn.1672-9315.2009.04.011 LI Jinkui,XIONG Zhenhua,LIU Dongsheng,et al. Numeric simulation of borehole pressure relief preventing roadway rockburst of a mine[J]. Journal of Xi’an University of Science and Technology,2009,29(4):424−426,432. doi: 10.3969/j.issn.1672-9315.2009.04.011
[8] 谭云亮,郭伟耀,赵同彬,等. 深部煤巷帮部失稳诱冲机理及“卸-固” 协同控制研究[J]. 煤炭学报,2020,45(1):66−81. TAN Yunliang,GUO Weiyao,ZHAO Tongbin,et al. Coal rib burst mechanism in deep roadway and “stress relief-support reinforcement” synergetic control and prevention[J]. Journal of China Coal Society,2020,45(1):66−81.
[9] 刘红岗,贺永年,徐金海,等. 深井煤巷钻孔卸压技术的数值模拟与工业试验[J]. 煤炭学报,2007,32(1):33−37. doi: 10.3321/j.issn:0253-9993.2007.01.007 LIU Honggang,HE Yongnian,XU Jinhai,et al. Numerical simulation and industrial test of boreholes destressing technology in deep coal tunnel[J]. Journal of China Coal Society,2007,32(1):33−37. doi: 10.3321/j.issn:0253-9993.2007.01.007
[10] 齐庆新,李一哲,赵善坤,等. 我国煤矿冲击地压发展70年:理论与技术体系的建立与思考[J]. 煤炭科学技术,2019,47(9):1−40. QI Qingxin,LI Yizhe,ZHAO Shankun,et al. Seventy years development of coal mine rockburst in China:establishment and consideration of theory and technology system[J]. Coal Science and Technology,2019,47(9):1−40.
[11] 朱斯陶,董续凯,姜福兴,等. 硫磺沟煤矿巨厚强冲击煤层掘进工作面超前钻孔卸压失效机理研究[J]. 采矿与安全工程学报,2022,39(1):45−53. ZHU Sitao,DONG Xukai,JIANG Fuxing,et al. Failure mechanism of pressure relief with advance drilling in driving face of strong burst ultra thick coal seam in Liuhuanggou coal mine[J]. Journal of Mining & Safety Engineering,2022,39(1):45−53.
[12] 刘冬桥,刘赫赫,王 炀,等. 钻孔卸压防治岩爆实验及破坏特征研究[J]. 岩石力学与工程学报,2023,42(1):100−114. LIU Dongqiao,LIU Hehe,WANG Yang,et al. Experiment study on drilling pressure relief for rockburst prevention and its failure characteristics[J]. Chinese Journal of Rock Mechanics and Engineering,2023,42(1):100−114.
[13] 王书文,潘俊锋,刘少虹,等. 基于能量耗散率的钻孔防冲效果评价方法[J]. 煤炭学报,2016,41(S2):297−304. WANG Shuwen,PAN Junfeng,LIU Shaohong,et al. Evaluation method for rockburst-preventing effects by drilling based on energy-dissipating rate[J]. Journal of China Coal Society,2016,41(S2):297−304.
[14] 张宏伟,李云鹏,陈 蓥,等. 三硬条件下孤岛区域大直径钻孔防冲方案优化[J]. 安全与环境学报,2017,17(5):1823−1827. ZHANG Hongwei,LI Yunpeng,CHEN Ying,et al. Research on optimizing large diameter drilling scheme of rockburst prevention in isolated area under three hard conditions[J]. Journal of Safety and Environment,2017,17(5):1823−1827.
[15] 吴建亭. 大直径长距离高位钻孔参数优化与实施[J]. 煤炭科学技术,2010,38(8):63−65,69. WU Jianting. Optimization and implementation on large diameter and long distance high level borehole parameters[J]. Coal Science and Technology,2010,38(8):63−65,69.
[16] 郑文贤,王 凯,李全中,等. 大直径钻孔“以孔代巷” 上隅角瓦斯治理参数优化及应用[J]. 中国矿业,2021,30(9):145−149. doi: 10.12075/j.issn.1004-4051.2021.09.007 ZHENG Wenxian,WANG Kai,LI Quanzhong,et al. Optimization and application of gas control parameters in the upper corner of large diameter borehole[J]. China Mining Magazine,2021,30(9):145−149. doi: 10.12075/j.issn.1004-4051.2021.09.007
[17] 赵阳升,冯增朝,万志军. 岩体动力破坏的最小能量原理[J]. 岩石力学与工程学报,2003,22(11):1781−1783. doi: 10.3321/j.issn:1000-6915.2003.11.005 ZHAO Yangsheng,FENG Zengchao,WAN Zhijun. Least energy priciple of dynamical failure of rock mass[J]. Chinese Journal of Rock Mechanics and Engineering,2003,22(11):1781−1783. doi: 10.3321/j.issn:1000-6915.2003.11.005
[18] LI Y K,ZHAO T B,LI Y F,et al. A five-parameter constitutive model for hysteresis shearing and energy dissipation of rock joints[J]. International Journal of Mining Science and Technology,2022,32(4):737−746. doi: 10.1016/j.ijmst.2022.05.002
[19] 沈明荣,陈建峰. 岩体力学[M]. 上海:同济大学出版社,2006:153–159. [20] 谢和平,鞠 杨,黎立云. 基于能量耗散与释放原理的岩石强度与整体破坏准则[J]. 岩石力学与工程学报,2005,24(17):3003−3010. doi: 10.3321/j.issn:1000-6915.2005.17.001 XIE Heping,JU Yang,LI Liyun. Criteria for strength and structural failure of rocks based on energy dissipation and energy release principles[J]. Chinese Journal of Rock Mechanics and Engineering,2005,24(17):3003−3010. doi: 10.3321/j.issn:1000-6915.2005.17.001
[21] 赵同彬,郭伟耀,谭云亮,等. 煤厚变异区开采冲击地压发生的力学机制[J]. 煤炭学报,2016,41(7):1659−1666. ZHAO Tongbin,GUO Weiyao,TAN Yunliang,et al. Mechanics mechanism of rock burst caused by mining in the variable region of coal thickness[J]. Journal of China Coal Society,2016,41(7):1659−1666.
[22] 贾传洋,蒋宇静,张学朋,等. 大直径钻孔卸压机理室内及数值试验研究[J]. 岩土工程学报,2017,39(6):1115−1122. doi: 10.11779/CJGE201706018 JIA Chuanyang,JIANG Yujing,ZHANG Xuepeng,et al. Laboratory and numerical experiments on pressure relief mechanism of large-diameter boreholes[J]. Chinese Journal of Geotechnical Engineering,2017,39(6):1115−1122. doi: 10.11779/CJGE201706018
[23] 宋大钊. 冲击地压演化过程及能量耗散特征研究[D]. 徐州:中国矿业大学,2012:64-71 SONG Dazhao. Research on rockburst evolutionary process and energy dissipation characteristics[D]. Xuzhou:China University of Mining and Technology,2012:64-71.
[24] 王 猛,王襄禹,肖同强. 深部巷道钻孔卸压机理及关键参数确定方法与应用[J]. 煤炭学报,2017,42(5):1138−1145. WANG Meng,WANG Xiangyu,XIAO Tongqiang. Borehole destressing mechanism and determination method of its key parameters in deep roadway[J]. Journal of China Coal Society,2017,42(5):1138−1145.
[25] 李永恩,郭晓菲,马念杰,等. 孔洞围岩塑性区边界计算的理论研究现状与分析评价[J]. 煤炭科学技术,2021,49(5):141−150. LI Yongen,GUO Xiaofei,MA Nianjie,et al. Research status and evaluation of theoretical calculation of plastic zone boundary for hole surrounding rock[J]. Coal Science and Technology,2021,49(5):141−150.
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