不同卸围压速率下煤样卸荷破坏能量演化特征
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摘要
岩体破坏实际上是在能量驱动下的一种状态失稳现象,其变形破坏过程中的能量演化规律能够反映岩体变形破坏的本质特征。为探求煤样破坏过程中能量的演化规律,对其进行了常规三轴及不同卸围压速率的三轴卸围压试验。试验结果表明:不同试验路径下,煤样在峰值应力前以能量的存储及耗散为主,在峰值应力后以能量的释放及耗散为主;煤样在较高的卸围压速率下,卸荷段经历时间较短,内部裂纹扩展及环向变形不充分,耗散能和克服围压做功耗能都较小,大量的能量在破裂时释放出来,破裂更加剧烈;同时,卸围压速率越快,煤样在破裂前后损伤量增加速率越快,损伤曲线急剧增高,因此,高应力煤岩体在开挖卸荷时,在岩体开挖施工速度较快时,极易引起大量积聚能量的突然释放,造成严重的灾害。
Rock damage is considered as a state of instability phenomenon under the driving of energy, the law of energy evolution in the process of deformation and failure can reflect the essential characteristics of rock mass deformation and failure. The loading and unloading tests were carried out on coal samples to explore the laws of energy evolution under different unloading confining pressure rates. The experimental results show that before the peak stress, the coal sample mainly experiences the energy storage and dissipation, whereas it mainly experiences the energy release and dissipation after the peak stress. It is found that when the unloading confining pressure rate is high, the duration of unloading confining pressure is short, the internal cracks of coal sample extend and circumferentially deform insufficiently, and the powers for energy dissipation and overcoming confining pressures are small. Moreover, most of the energy release when the coal sample ruptures, which make the coal sample damage seriously. Meanwhile, when the unloading confining pressure rate is larger, the damage rate of the coal sample increases faster before and after the rupture, which results in the sharp increase of the damage curve. Therefore, when the high-stress coal is excavated with a high construction speed, it is easy to cause a sudden release of a large amount of accumulated energy, causing serious disasters.
Rock damage is considered as a state of instability phenomenon under the driving of energy, the law of energy evolution in the process of deformation and failure can reflect the essential characteristics of rock mass deformation and failure. The loading and unloading tests were carried out on coal samples to explore the laws of energy evolution under different unloading confining pressure rates. The experimental results show that before the peak stress, the coal sample mainly experiences the energy storage and dissipation, whereas it mainly experiences the energy release and dissipation after the peak stress. It is found that when the unloading confining pressure rate is high, the duration of unloading confining pressure is short, the internal cracks of coal sample extend and circumferentially deform insufficiently, and the powers for energy dissipation and overcoming confining pressures are small. Moreover, most of the energy release when the coal sample ruptures, which make the coal sample damage seriously. Meanwhile, when the unloading confining pressure rate is larger, the damage rate of the coal sample increases faster before and after the rupture, which results in the sharp increase of the damage curve. Therefore, when the high-stress coal is excavated with a high construction speed, it is easy to cause a sudden release of a large amount of accumulated energy, causing serious disasters.
引文
[1]谢和平,彭瑞东,鞠杨.岩石变形破坏过程中的能量耗散分析[J].岩石力学与工程学报,2004,23(21):3565-3570.XIE He-ping,PENG Rui-dong,JU Yang.Energy dissipation of rock deformation and fracture[J].Chinese Journal of Rock Mechanics and Engineering,2004,23(21):3565-3570.
[2]翟明磊,郭保华,李冰洋,等.岩石节理分级剪切加载-蠕变-卸载的能量与变形特征[J].岩土力学,2018,39(8):2865-2872+2885.ZHAI Ming-lei,GUO Bao-hua,LI Bing-yang,et al.Energy and deformation characteristics of rock joints under multi-stage shear loading-creep-unloading conditions[J].Rock and Soil Mechanics,2018,39(8):2865-2872+2885.
[3]陈子全,何川,董唯杰,等.北疆侏罗系与白垩系泥质砂岩物理力学特性对比分析及其能量损伤演化机制研究[J].岩土力学,2018,39(8):2873-2885.CHEN Zi-quan,HE Chuan,DONG Wei-jie,et al.Physico-mechanical properties and its energy damage evolution mechanism of the Jurassic and Cretaceous argillaceous sandstone in Northern Xinjiang[J].Rock and Soil Mechanics,2018,39(8):2873-2885.
[4]黄达,黄润秋,张永兴.粗晶大理岩单轴压缩力学特性的静态加载速率效应及能量机制试验研究[J].岩石力学与工程学报,2012,31(2):245-255.HUANG Da,HUANG Run-qiu,ZHANG Yong-xing.Experimental investigations on static loading rate effects on mechanical properties and energy mechanism of coarse crystal grain marble under uniaxial compression[J].Chinese Journal of Rock Mechanics and Engineering,2012,31(2):245-255.
[5]张志镇,高峰.单轴压缩下红砂岩能量演化试验研究[J].岩石力学与工程学报,2012,31(5):953-962.ZHANG Zhi-zhen,GAO Feng.Experimental research on energy evolution of red sandstone samples under uniaxial compression[J].Chinese Journal of Rock Mechanics and Engineering,2012,31(5):953-962.
[6]张志镇,高峰.单轴压缩下岩石能量演化的非线性特性研究[J].岩石力学与工程学报,2012,31(6):1198-1207.ZHANG Zhi-zhen,GAO Feng.Research on nonlinear characteristics of rock energy evolution under uniaxial compression[J].Chinese Journal of Rock Mechanics and Engineering,2012,31(6):1198-1207.
[7]宋义敏,杨小彬.煤柱失稳破坏的变形场及能量演化试验研究[J].采矿与安全工程学报,2013,30(6):822-827.SONG Yi-min,YANG Xiao-bin.Evolution characteristics of deformation and energy fields during coal pillar instability[J].Journal of Mining&Safety Engineering,2013,30(6):822-827.
[8]张辉,程利兴,李国盛.基于巴西劈裂法的饱水煤样能量耗散特征研究[J].实验力学,2016,31(4):534-542.ZHANG Hui,CHENG Li-xing,LI Guo-sheng.Study of energy dissipation characteristics of saturated coal sample based on Brazil splitting method[J].Journal of Experimental Mechanics,2016,31(4):534-542.
[9]田勇,俞然刚.不同围压下灰岩三轴压缩过程能量分析[J].岩土力学,2014,35(1):118-122+129.TIAN Yong,YU Ran-gang.Energy analysis of limestone during triaxial compression under different confining pressures[J].Rock and Soil Mechanics,2014,35(1):118-122+129.
[10]陈学章,何江达,肖明砾,等.三轴卸荷条件下大理岩扩容与能量特征分析[J].岩土工程学报,2014,36(6):1106-1112.CHEN Xue-zhang,HE Jiang-da,XIAO Ming-li,et al.Dilatancy and energy properties of marble under triaxial unloading condition[J].Chinese Journal of Geotechnical Engineering,2014,36(6):1106-1112.
[11]张后全,徐建峰,贺永年,等.脆性岩石真三轴能量强度准则研究[J].中国矿业大学学报,2012,41(4):564-570.ZHANG Hou-quan,XU Jian-feng,HE Yong-nian,et al.Study of triaxial energy strength criterion for brittle rock materials[J].Journal of China University of Mining&Technology,2012,41(4):564-570.
[12]丛宇,王在泉,郑颖人,等.不同卸荷路径下大理岩破坏过程能量演化规律[J].中南大学学报(自然科学版),2016,47(9):3140-3147.CONG Yu,WANG Zai-quan,ZHENG Ying-ren,et al.Energy evolution principle of fracture propagation of marble with different unloading stress paths[J].Journal of Central South University(Science and Technology),2016,47(9):3140-3147.
[13]陈卫忠,吕森鹏,郭小红,等.基于能量原理的卸围压试验与岩爆判据研究[J].岩石力学与工程学报,2009,28(8):1530-1540.CHEN Wei-zhong,LüSen-peng,GUO Xiao-hong,et al.Research on unloading confining pressure tests and rockburst criterion based on energy theory[J].Chinese Journal of Rock Mechanics and Engineering,2009,28(8):1530-1540.
[14]潘岳,王志强,李爱武.岩石失稳破裂的综合刚度和综合能量准则[J].岩土力学,2009,30(12):3671-3676.PAN Yue,WANG Zhi-qiang,LI Ai-wu.Comprehensive rigidity and comprehensive energy criterion of the rock burst[J].Rock and Soil Mechanics,2009,30(12):3671-3676.
[15]KACHANOV L M.Time rupture process under creep conditions[J].Izvestia Akademii Nauk.SSSR,Otdelenie Tekhnicheskich Nauk,1958,2(8):26-31.
[16]刘保县,黄敬林,王泽云,等.单轴压缩煤岩损伤演化及声发射特性研究[J].岩石力学与工程学报,2009,28(增刊1):3234-3238.LIU Bao-xian,HUANG Jing-lin,WANG Ze-yun,et al.Study on damage evolution and acoustic emission character of coal-rock under uniaxial compression[J].Chinese Journal of Rock Mechanics and Engineering,2009,28(Suppl.1):3234-3238.
[2]翟明磊,郭保华,李冰洋,等.岩石节理分级剪切加载-蠕变-卸载的能量与变形特征[J].岩土力学,2018,39(8):2865-2872+2885.ZHAI Ming-lei,GUO Bao-hua,LI Bing-yang,et al.Energy and deformation characteristics of rock joints under multi-stage shear loading-creep-unloading conditions[J].Rock and Soil Mechanics,2018,39(8):2865-2872+2885.
[3]陈子全,何川,董唯杰,等.北疆侏罗系与白垩系泥质砂岩物理力学特性对比分析及其能量损伤演化机制研究[J].岩土力学,2018,39(8):2873-2885.CHEN Zi-quan,HE Chuan,DONG Wei-jie,et al.Physico-mechanical properties and its energy damage evolution mechanism of the Jurassic and Cretaceous argillaceous sandstone in Northern Xinjiang[J].Rock and Soil Mechanics,2018,39(8):2873-2885.
[4]黄达,黄润秋,张永兴.粗晶大理岩单轴压缩力学特性的静态加载速率效应及能量机制试验研究[J].岩石力学与工程学报,2012,31(2):245-255.HUANG Da,HUANG Run-qiu,ZHANG Yong-xing.Experimental investigations on static loading rate effects on mechanical properties and energy mechanism of coarse crystal grain marble under uniaxial compression[J].Chinese Journal of Rock Mechanics and Engineering,2012,31(2):245-255.
[5]张志镇,高峰.单轴压缩下红砂岩能量演化试验研究[J].岩石力学与工程学报,2012,31(5):953-962.ZHANG Zhi-zhen,GAO Feng.Experimental research on energy evolution of red sandstone samples under uniaxial compression[J].Chinese Journal of Rock Mechanics and Engineering,2012,31(5):953-962.
[6]张志镇,高峰.单轴压缩下岩石能量演化的非线性特性研究[J].岩石力学与工程学报,2012,31(6):1198-1207.ZHANG Zhi-zhen,GAO Feng.Research on nonlinear characteristics of rock energy evolution under uniaxial compression[J].Chinese Journal of Rock Mechanics and Engineering,2012,31(6):1198-1207.
[7]宋义敏,杨小彬.煤柱失稳破坏的变形场及能量演化试验研究[J].采矿与安全工程学报,2013,30(6):822-827.SONG Yi-min,YANG Xiao-bin.Evolution characteristics of deformation and energy fields during coal pillar instability[J].Journal of Mining&Safety Engineering,2013,30(6):822-827.
[8]张辉,程利兴,李国盛.基于巴西劈裂法的饱水煤样能量耗散特征研究[J].实验力学,2016,31(4):534-542.ZHANG Hui,CHENG Li-xing,LI Guo-sheng.Study of energy dissipation characteristics of saturated coal sample based on Brazil splitting method[J].Journal of Experimental Mechanics,2016,31(4):534-542.
[9]田勇,俞然刚.不同围压下灰岩三轴压缩过程能量分析[J].岩土力学,2014,35(1):118-122+129.TIAN Yong,YU Ran-gang.Energy analysis of limestone during triaxial compression under different confining pressures[J].Rock and Soil Mechanics,2014,35(1):118-122+129.
[10]陈学章,何江达,肖明砾,等.三轴卸荷条件下大理岩扩容与能量特征分析[J].岩土工程学报,2014,36(6):1106-1112.CHEN Xue-zhang,HE Jiang-da,XIAO Ming-li,et al.Dilatancy and energy properties of marble under triaxial unloading condition[J].Chinese Journal of Geotechnical Engineering,2014,36(6):1106-1112.
[11]张后全,徐建峰,贺永年,等.脆性岩石真三轴能量强度准则研究[J].中国矿业大学学报,2012,41(4):564-570.ZHANG Hou-quan,XU Jian-feng,HE Yong-nian,et al.Study of triaxial energy strength criterion for brittle rock materials[J].Journal of China University of Mining&Technology,2012,41(4):564-570.
[12]丛宇,王在泉,郑颖人,等.不同卸荷路径下大理岩破坏过程能量演化规律[J].中南大学学报(自然科学版),2016,47(9):3140-3147.CONG Yu,WANG Zai-quan,ZHENG Ying-ren,et al.Energy evolution principle of fracture propagation of marble with different unloading stress paths[J].Journal of Central South University(Science and Technology),2016,47(9):3140-3147.
[13]陈卫忠,吕森鹏,郭小红,等.基于能量原理的卸围压试验与岩爆判据研究[J].岩石力学与工程学报,2009,28(8):1530-1540.CHEN Wei-zhong,LüSen-peng,GUO Xiao-hong,et al.Research on unloading confining pressure tests and rockburst criterion based on energy theory[J].Chinese Journal of Rock Mechanics and Engineering,2009,28(8):1530-1540.
[14]潘岳,王志强,李爱武.岩石失稳破裂的综合刚度和综合能量准则[J].岩土力学,2009,30(12):3671-3676.PAN Yue,WANG Zhi-qiang,LI Ai-wu.Comprehensive rigidity and comprehensive energy criterion of the rock burst[J].Rock and Soil Mechanics,2009,30(12):3671-3676.
[15]KACHANOV L M.Time rupture process under creep conditions[J].Izvestia Akademii Nauk.SSSR,Otdelenie Tekhnicheskich Nauk,1958,2(8):26-31.
[16]刘保县,黄敬林,王泽云,等.单轴压缩煤岩损伤演化及声发射特性研究[J].岩石力学与工程学报,2009,28(增刊1):3234-3238.LIU Bao-xian,HUANG Jing-lin,WANG Ze-yun,et al.Study on damage evolution and acoustic emission character of coal-rock under uniaxial compression[J].Chinese Journal of Rock Mechanics and Engineering,2009,28(Suppl.1):3234-3238.