(1. Beijing Research Center of Urban System Engineering，Beijing 100035，China；2. Mine Safety Branch，China Coal Research Institute，Beijing 100013，China；3. School of Safety Engineering，China University of Mining and Technology，Xuzhou，Jiangsu 221116，China；4. Department of Mining and Design，Tiandi Science and Technology Company Limited，Beijing 100013，China)
Abstract：In order to research the mechanism of coal and gas outburst from boreholes induced by the water jet technique for enhancing coal permeability，theoretical analysis of coal mass instability conditions and single factor test in underground field were carried out，and coal rock electromagnetic radiations(EMR) and gas emissions from boreholes were monitored based on the hydraulic slotting technique in high-gas coal seams. The action mechanisms of in-situ stresses and gas pressure on coal mass instability with hydraulic slotting and their influence characteristics were demonstrated. The results show that slotting expansion can enhance the effect of in-situ stresses and gas gradient force around the borehole and that the minimum critical pressure value of the water jet with enough impacting time is needed for the coal body to outburst in the borehole. It is also shown that the flow pressure of water jet has a linear positive correlation with the weight of coal debris discharged from boreholes while a linear negative correlation with the time of initial outburst occurring. Decreasing of the gas pressure around the borehole would weak the effect of coal mass instability ejection. The phenomena that the coal and rock EMR signal fluctuates sharply during the unstable ejection and the EMR energy level decreases after slotting reflect the instability influenced by the in-situ stress，and the phenomenon that the instantaneous gas emission from the gas pre-discharge borehole decreases obviously after slotting reflects the instability influenced by the gas pressure. The research conclusions provide a reference for the prevention and control of borehole ejection in the application of hydraulic slotting technology.
沈春明1，2，3，林柏泉3，王维华2，张慧杰2，韩 雷4. 水力切槽高瓦斯煤体失稳发生机制与试验分析[J]. 岩石力学与工程学报, 2019, 38(10): 1979-1988.
SHEN Chunming1，2，3，LIN Baiquan3，WANG Weihua2，ZHANG Huijie2，HAN Lei4. Field test analysis of instability mechanisms of high gas coal seams induced by hydraulic slotting. , 2019, 38(10): 1979-1988.
[1] 袁 亮，林柏泉，杨 威. 我国煤矿水力化技术瓦斯治理研究进展及发展方向[J]. 煤炭科学技术，2015，43(1)：45–49.(YUAN Liang，LIN Baiquan，YANG Wei. Research progress and development direction of gas control with mine hydraulic technology in China coal mine[J]. Coal Science and Technology，2015，43(1)：45–49.(in Chinese))
[2] LU Y Y，GE Z L，YANG F，et al. Progress on the hydraulic measures for grid slotting and fracking to enhance coal seam permeability[J]. International Journal of Mining Science and Technology，2017，27(5)：867–871.
[3] 邹全乐，林柏泉，刘 厅，等. 割缝预抽后煤瓦斯吸附特性的变化特征[J]. 岩石力学与工程学报，2014，33(10)：2 117–2 124.(ZOU Quanle，LIN Baiquan，LIU Ting，et al. Variation of gas adsorption of coal after hydraulic slotting and pre-draining[J]. Chinese Journal of Rock Mechanics and Engineering，2014，33(10)：2 117–2 124.(in Chinese))
[4] 张永将，黄振飞，李成成. 高压水射流环切割缝自卸压机制与应用[J]. 煤炭学报，2018，43(11)：3 016–3 022.(ZHANG Yongjiang，HUANG Zhenfei，LI Chengcheng. Investigation and application of high pressure water jet annularity slotting self pressure release mechanism[J]. Journal of China Coal Society，2018，43(11)：3 016– 3 022.(in Chinese))
[5] 高亚斌，林柏泉，杨 威，等. 高突煤层穿层钻孔“钻–冲–割”耦合卸压技术及应用[J]. 采矿与安全工程学报，2017，34(1)：177–184.(GAO Yabin，LIN Baiquan，YANG Wei，et al. “Drilling- flushing-slotting” intercoupling pressure-relief technology of cross- measure boreholes and its application in high gassy outburst coal seam[J]. Journal of Mining and Safety Engineering，2017，34(1)：177–184.(in Chinese))
[6] 聂百胜，马延崑，孟筠青，等. 中等尺度煤与瓦斯突出物理模拟装置研制与验证[J]. 岩石力学与工程学报，2018，37(5)：1 218–1 225. (NIE Baisheng，MA Yankun，MENG Junqing，et al. Middle scale simulation system of coal and gas outburst[J]. Chinese Journal of Rock Mechanics and Engineering，2018，37(5)：1 218–1 225.(in Chinese))
[7] 赵志强，靳俊晓，申金超. 石门揭煤中煤体塑性区跃迁特征与诱突机制[J]. 岩石力学与工程学报，2019，38(2)：343–351.(ZHAO Zhiqiang，JIN Junxiao，SHEN Jinchao. Promotion characteristics and induced outburst mechanisms of coal plastic zones in rock cross-cut coal uncovering[J]. Chinese Journal of Rock Mechanics and Engineering，2019，38(2)：343–351.(in Chinese))
[8] 吴立云，王 飞，杨玉中. 煤层瓦斯流动方程研究及应用[J]. 采矿与安全工程学报，2016，33(5)：951–956.(WU Liyun，WANG Fei，YANG Yuzhong. Research on equation of gas flow in the coal seam and its application[J]. Journal of Mining and Safety Engineering，2016，33(5)：951–956.(in Chinese))
[9] ZHOU H X，GAO J，HAN K，et al. Permeability enhancements of borehole outburst cavitation in outburst-prone coal seams[J]. International Journal of Rock Mechanics and Mining Sciences，2018，111：12–20.
[10] 郝富昌，孙丽娟，左伟芹. 考虑流变特性的水力冲孔孔径变化规律及防堵孔技术[J]. 煤炭学报，2016，41(6)：1 434–1 440.(HAO Fuchang，SUN Lijuan，ZUO Weiqin. Hydraulic flushing aperture variation and anti-blocking technology considering rheological property[J]. Journal of China Coal Society，2016，41(6)：1 434–1 440. (in Chinese))
[11] 刘 勇，何 岸，魏建平，等. 水射流卸压增透堵孔诱因及解堵新方法[J]. 煤炭学报，2016，41(8)：1 963–1 967.(LIU Yong，HE An，WEI Jianping，et al. Research of plugging factor and new plugging method to hydraulic relieving stress[J]. Journal of China Coal Society，2016，41(8)：1 963–1 967.(in Chinese))
[12] 徐 全，黄渊跃，刘学服，等. 高压水射流条件下钻孔喷孔防治研究[J]. 煤炭技术，2014，33(12)：148–150.(XU Quan，HUANG Yuanyue，LIU Xuefu，et al. Study on jet orifice prevention under high- pressure water Jet[J]. Coal Technology，2014，33(12)：148–150.(in Chinese))
[13] 孙矩正，李东洋，粟登峰，等. 高压水射流割缝诱导钻孔喷孔机理及防治措施[J]. 煤矿安全，2016，47(2)：136–139.(SUN Juzheng，LI Dongyang，SU Dengfeng，et al. Mechanism of drilling jet orifice induced by high pressure water jet cutting and its control measures[J]. Safety in Coal Mines，2016，47(2)：136–139.(in Chinese))
[14] 郑春山. 穿层钻孔煤或瓦斯喷出机理及防治关键技术研究[硕士学位论文][D]. 徐州：中国矿业大学，2014.(ZHENG Chunshan. Study on the mechanism and critical control technique of coal or gas spurt in the cross-rock-layer drilling[M. S. Thesis][D]. Xuzhou：China University of Mining and Technology，2014.(in Chinese))
[15] 沈春明，汪 东，张 浪，等. 水射流切槽诱导高瓦斯煤体失稳喷出机制与应用[J]. 煤炭学报，2015，40(9)：2 097–2 104.(SHEN Chunming，WANG Dong，ZHANG Lang，et al. Mechanism and application of inducing high-gas coal outburst from borehole by waterjet slotting[J]. Journal of China Coal Society，2015，40(9)： 2 097–2 104.(in Chinese))
[16] LIN B Q，SHEN C M. Coal permeability-improving mechanism of multilevel slotting by water jet and application in coal mine gas extraction[J]. Environmental Earth Sciences，2015，73：5 975–5 986.
[17] 倪红坚，王瑞和，葛洪魁. 高压水射流破岩的数值模拟分析[J]. 岩石力学与工程学报，2004，23(4)：550–554.(NI Hongjian，WANGRuihe，GE Hongkui. Numerical simulation on rock breaking under high pressure water jet[J]. Chinese Journal of Rock Mechanics and Engineering，2004，23(4)：550–554.(in Chinese))
[18] FIELD J E. ELSI conference：invited lecture：liquid impact：theory，experiment，applications[J]. Wear，1999，233–235：1–12.
[19] 董方庭，宋宏伟，郭志宏，等. 巷道围岩松动圈支护理论[J]. 煤炭学报，1994，(1)：21–32.(DONG Fangting，SONG Hongwei，GUO Zhihong，et al. Theory of roadway surrounding rock loose circle support[J]. Journal of China Coal Society，1994，(1)：21–32.(in Chinese))
[20] 齐黎明，祁 明，陈学习. 抽采钻孔周围煤层瓦斯压力分布理论分析及应用[J]. 中国安全科学学报，2018，28(7)：102–108.(QI Liming，QI Ming，CHEN Xuexi. Theoretical analysis of coal seam gas pressure distribution around drainage hole and its application[J]. China Safety Science Journal，2018，28(7)：102–108.(in Chinese))
[21] 舒龙勇，王 凯，齐庆新，等. 煤与瓦斯突出关键结构体致灾机制[J]. 岩石力学与工程学报，2017，36(2)：347–356.(SHU Longyong，WANG Kai，QI Qingxin，et al. Key structural body theory of coal and gas outburst[J]. Chinese Journal of Rock Mechanics and Engineering，2017，36(2)：347–356.(in Chinese))
[22] LIN B Q，YAN F Z，ZHU C J，et al. Cross-borehole hydraulic slotting technique for preventing and controlling coal and gas outbursts during coal roadway excavation[J]. Journal of Natural Gas Science and Engineering，2015，26：518–525.
[23] 潘一山，徐连满，李国臻，等. 煤矿深井动力灾害电荷辐射特征及应用[J]. 岩石力学与工程学报，2014，33(8)：1 619–1 624.(PAN Yisan，XU Lianman，LI Guozhen，et al. Characteristics of charge radiation of dynamic disasters in deep coal mine[J]. Chinese Journal of Rock Mechanics and Engineering，2014，33(8)：1 619–1 624.(in Chinese))
[24] 窦林名，何学秋，REN T，等. 动静载叠加诱发煤岩瓦斯动力灾害原理及防治技术[J]. 中国矿业大学学报，2018，47(1)：48–59.(DOU Linming，HE Xueqiu，REN T，et al. Mechanism of coal-gas dynamic disasters caused by the superposition of static and dynamic loads and its control technology[J]. Journal of China University of Mining and Technology，2018，47(1)：48–59.(in Chinese))
2019, Vol. 38 
