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| Multi-scale damage evolution characteristics of coal and rock under hydraulic coupling |
| LAI Xingping1,2,3,ZHANG Shuai1,DAI Jingjing1,WANG Zeyang1,XU Huicong1 |
| (1. College of Energy Science and Engineering,Xi′an University of Science and Technology,Xi'an,Shaanxi 710054,China;
2. State Key Laboratory of Coal Resources in Western China,Xi′an University of Science and Technology,Xi'an,Shaanxi 710054,China;3. Key Laboratory of Western Mine Exploration and Hazard Prevention,Ministry of Education,Xi′an University of Science and Technology,Xi'an,Shaanxi 710054,China) |
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Abstract Hydraulic coupling has an important influence on mechanical properties of deep coal and rock mass and failure mode. In order to study the softening effect of uni-axial compression of coal and rock samples and multi-scale characteristics of damage evolution. Utilizing the rock mechanical testing system and acoustical emission monitoring system,the uni-axial compression test of coal and rock samples is developed under the different water conditions. Firstly,by means of scanning electron microscopic identification of micro-structure. Secondly,the mechanical properties of coal and rock samples and failure mode is analyzed from macro scale. Thirdly,the damage evolution process of coal and rock samples is retrieved from the meso-scale based on acoustic emission parameters. Finally,the evolution characteristics of macro-and meso-scale damage is discussed under hydraulic coupling. The result shows that the macroscopic softening effects of coal and rock samples in different water-bearing states are similar. The increase of water content can effectively softening of rock mechanics parameters of coal as well as softening effect of distinct phases for the state has low water content,the softening effects of coal and rock samples in different water-bearing states are obviously different. The acoustic emission parameters of coal samples show a softening trend as the moisture content increases. Rock acoustic emission parameters,with the water rate increases,showing reduce the increasing trend in first. It shows that the water can effectively slow the damage evolution of coal sampling process. Ultimately,the impact of the coal sample bias is weakened. While the higher water content to provide rigidity and pore water coupling of water film speeds up the process of rock damage evolution. Finally,it is contrary to the theory of rock burst prevention and control to reduce the severity of rock mass failure. This study conclusion provides the theoretical basis for prevention measures of deep water softening of coal and rock burst.
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| [1] 谢和平. 深部岩体力学与开采理论研究进展[J]. 煤炭学报,2019,44(5):1 283–1 305.(XIE Heping. Research review of the state key research development program of China:deep rock mechanics and mining theory[J]. Journal of China Coal Society,2019,44(5):1 283– 1 305.(in Chinese))
[2] 李 东,姜福兴,陈 洋,等. 深井富水工作面“动–静”应力效应诱发冲击地压机制研究[J]. 岩土工程学报,2018,40(9):1 714– 1 722.(LI Dong,JIANG Fuxing,CHEN Yang,et al. Study on mechanism of rock burst induced by "dynamic-static" stress effect in water-rich working face of deep well[J]. Journal of Geotechnical Engineering,2018,40(9):1 714–1 722.(in Chinese))
[3] 李宏艳,莫云龙,孙中学,等. 煤矿冲击地压灾害防控技术研究现状及展望[J]. 煤炭科学技术,2019,47(1):62–68.(LI Hongyan,MO Yunlong,SUN Zhongxue,et al. Research status and prospect of coal bumps prevention and control technology[J]. Coal Science and Technology,2019,47(1):62–68.(in Chinese))
[4] 赵阳升. 多孔介质多场耦合作用及其工程响应[M]. 北京:科学出版社,2010:1–8.(ZHAO Yangsheng. Multi-field coupling in porous media and its engineering response[M]. Beijing:Science Press,2010:1–8.(in Chinese))
[5] 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. Study on key technology of monitoring and solving danger of rock burst in deep mining of coal mine[J]. Journal of China Coal Society,2019,44(1):160–172.(in Chinese))
[6] 来兴平,蔡美峰. 基于非平衡统计的塌陷区岩体断裂失稳声发射信号分析[J]. 岩石力学与工程学报,2004,23(2):272–276.(LAI Xingping,CAI Meifeng. Acoustic emission signal analysis of fracture instability of rock mass in subsidence area based on non-equilibrium statistics[J]. Chinese Journal of Rock Mechanics and Engineering,2004,23(2):272–276.(in Chinese))
[7] HAWKINS A B,MCCONNELL B J. Sensitivity of sandstone strength and deformability to changes in moisture content[J]. Journal of Engineering Geology and Hydrogeology,1992,25(2):115–130.
[8] PERERA M S A,RANJITH P G,PETER M. Effects of saturation medium and pressure on strength parameters valley brown coal:carbon dioxide,water and nitrogen saturations[J]. Energy,2011,36(12):6 941–6 947.
[9] PAN Z,CONNELL L D,MICHAEL C,et al. Effects of matrix moisture on gas diffusion and flow in coal[J]. Fuel,2010,89(11): 3 207–3 217.
[10] 王 文,李化敏,顾合龙. 三维动静组合加载含水煤样强度特征试验研究[J]. 岩石力学与工程学报,2017,36(10):2 406–2 414. (WANG Wen,LI Huamin,GU Hailong. Experimental study on strength characteristics of water-bearing coal samples under three-dimensional dynamic and static loading[J]. Chinese Journal of Rock Mechanics and Engineering,2017,36(10):2 406–2 414.(in Chinese))
[11] 李波波,李建华,杨 康,等. 考虑含水率影响的煤岩变形及渗透率模型[J]. 煤炭学报,2019,44(4):1 076–1 083.(LI Bobo,LI Jianhua,YANG Kang,et al. Deformation and permeability model of coal and rock considering moisture content[J]. Journal of China Coal Society,2019,44(4):1 076–1 083.(in Chinese))
[12] 赵 程,幸金权,牛佳伦,等. 水–力共同作用下预制裂隙类岩石试样裂纹扩展试验研究[J]. 岩石力学与工程学报,2019,38(增1):2 823–2 830.(ZHAO Cheng,XING Jinquan,NIU Jialun,et al. Experimental study on crack propagation of precrack rock-like specimens under hydro-mechanical coupling[J]. Chinese Journal of Rock Mechanics and Engineering,2019,38(Supp.1):2 823–2 830. (in Chinese))
[13] 邓华锋,支永艳,段玲玲,等. 水–岩作用下砂岩力学特性及微细观结构损伤演化[J]. 岩土力学,2019,40(9):1–10.(DENG Huafeng,ZHI Yongyan,DUAN Lingling,et al. Experimental study on crack propagation of precrack rock-like specimens under hydro-mechanical coupling[J]. Rock and Soil Mechanics,2019,40(9):1–10.(in Chinese))
[14] 夏 冬,杨天鸿,徐 涛,等. 浸水时间对饱水岩石损伤破坏过程中声发射特征影响的试验[J]. 煤炭学报,2015,40(增2):337–345.(XIA Dong,YANG Tianhong,XU Tao,et al. Experimental study on AE properties during the damage process of water-saturated rock specimens based on time effect[J]. Journal of China Coal Society,2015,40(Supp.2):337–345.(in Chinese))
[15] 张艳博,梁 鹏,孙 林,等. 单轴压缩下饱水花岗岩破裂过程声发射频谱特征试验研究[J]. 岩土力学,2019,40(7):2 497–2 506. (ZHANG Yanbo,LIANG Peng,SUN Lin,et al. Experimental study on acoustic emission spectrum characteristics of saturated granite fracture process under uniaxial compression[J]. Rock and Soil Mechanics,2019,40(7):2 497–2 506.(in Chinese))
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