应力条件对受载煤体声发射活动特征的影响研究
|
摘要
为研究外部应力条件对受载煤体的声发射活动特征的影响作用,采用岩石力学试验系统和声发射仪,开展了单轴、不同围压三轴、卸围压三类应力条件下的煤样破坏试验,对比分析了煤体在不同应力条件下的破坏特征及声发射活动特征。试验结果表明:煤体的声发射活动宏观上与煤体的破坏阶段相对应,应力条件对煤的破坏特征及声发射活动特征具有重要影响作用。在增围压作用下,煤体的弹性模量、强度增加,主破裂面与轴向加载方向的角度逐渐增大,主破裂机制由张拉破坏向剪切破坏转变;在卸围压作用下,煤的主破裂机制由剪切破坏向张拉破坏转变。在围压应力增加条件下,在弹性变形阶段,煤体的声发射事件显著减少;在屈服变形阶段,声发射事件的能量逐步降低,并且能量的分布形态从相对"聚集"向相对"分散"的转变;在峰后变形阶段,煤体呈现渐进损伤的延性破坏特征,声发射活动持续逐步降低。在三轴卸载围压应力条件下,在煤体屈服阶段,声发射事件率与能量都随着应力的快速跌落而迅速增加,声发射活动趋于活跃,煤体的破坏方式最为剧烈。
In order to study the effect of external stress condition on AE activity of loaded coal in the failure process,coal failure experiments under 3 kinds of stress condition,uniaxial,conventional triaxial,and unloading confining stress,are carried out with rock mechanics testing machine and AE monitoring instrument,the corresponding failure and AE activity characteristics of coal are compared and analyzed.The results show that AE activity of coal,in macro perspective,is related to phases of coal failure process,and the stress condition has an important influence on the failure characteristic and AE activity of coal.Under the effect of confining stress increasing,elastic modulus and strength increase,the main fracture angle to axial main stress direction is increasing,and main failure mechanism changes gradually from brittle tensile to shear failure,and the contrary mechanism change when confining stress unloading.In condition of confining stress increasing,AE event reduces in phase of elastic deformation; in phase of yield deformation,the general energy level of AE event is decreasing,and the energy distribution of AE events is transforming from relative disperse condition to relative concentration condition with the increasing of confining stress; and in phase of post-peak,the damage of coal shows progressive failure characteristics and the AE activity keeps gradually decreasing.In condition of confining stress unloading,and the AE event rate and energy increase rapidly with rapid drop of axial stress,the failure mode of coal is the most drastic in all stress conditions.
In order to study the effect of external stress condition on AE activity of loaded coal in the failure process,coal failure experiments under 3 kinds of stress condition,uniaxial,conventional triaxial,and unloading confining stress,are carried out with rock mechanics testing machine and AE monitoring instrument,the corresponding failure and AE activity characteristics of coal are compared and analyzed.The results show that AE activity of coal,in macro perspective,is related to phases of coal failure process,and the stress condition has an important influence on the failure characteristic and AE activity of coal.Under the effect of confining stress increasing,elastic modulus and strength increase,the main fracture angle to axial main stress direction is increasing,and main failure mechanism changes gradually from brittle tensile to shear failure,and the contrary mechanism change when confining stress unloading.In condition of confining stress increasing,AE event reduces in phase of elastic deformation; in phase of yield deformation,the general energy level of AE event is decreasing,and the energy distribution of AE events is transforming from relative disperse condition to relative concentration condition with the increasing of confining stress; and in phase of post-peak,the damage of coal shows progressive failure characteristics and the AE activity keeps gradually decreasing.In condition of confining stress unloading,and the AE event rate and energy increase rapidly with rapid drop of axial stress,the failure mode of coal is the most drastic in all stress conditions.
引文
[1]胡千庭,文光才.煤与瓦斯突出的力学作用机理[M].北京:科学出版社,2013.
[2]潘一山.煤与瓦斯突出、冲击地压复合动力灾害一体化研究[J].煤炭学报,2016,41(1):105-112.PAN Yishan. Integrated study on compound dynamic disaster of coal-gas outburst and rockburst[J].Journal of China Coal Society,2016,41(1):105-112.
[3]杨慧明.深部应力型突出灾害的声发射监测工艺及预警试验研究[J].煤矿安全,2017,48(2):17-20.YANG Huiming. Experimental study on acoustic emission monitoring technique and pre-warning of stress type outburst disasters in deep mine[J].Safety in Coal Mines,2017,48(2):17-20.
[4]吕贵春,邹银辉,李建功,等.基于AE传播规律监测急倾煤层掘进期动力现象[J].煤炭科学技术,2010,38(5):62-65.LYU Guichun,ZOU Yinhui,LI Jiangong,et al. Monitoring and measuring dynamic phenomenon of gateway driving in steep inclined seam based on AE transmission law[J].Coal Science and Technology,2010,38(5):62-65.
[5] MOGI K.Study of Elastic Shocks Caused by the Fracture of Heterogeneous Materials and its Relations to Earthquake Phenomena[J].Bull Earthq Res Inst,1962,40(1):125-173.
[6]张茹,谢和平,刘建锋,等.单轴多级加载岩石破坏声发射特性试验研究[J].岩石力学与工程学报,2006,25(12):2584-2588.ZHANG Ru,XIE Heping,LIU Jianfeng et al.Experimental study on acoustic emission characteristics of rock failure under uniaxial multilevel loadings[J].Chinese Journal of Rock Mechanics and Engineering,2006,25(12):2584-2588.
[7]曹树刚,刘延保,张立强.突出煤体变形破坏声发射特征的综合分析[J].岩石力学与工程学报,2007,26(S1):2794-2799.CAO Shugang,LIU Yanbao,ZHANG Liqiang.Study on characteristics of acoustic emission in outburst coal[J]. Chinese Journal of Rock Mechanics and Engineering,2007,26(S1):2794-2799.
[8]杨慧明.塑性煤与脆性煤破坏过程的声发射演化特征试验研究[J].矿业安全与环保,2015,42(1):9-12.YANG Huiming.Test study on acoustic emission evolution characteristics in failure process of plastic and brittle coal[J]. Mining Safety&Environmental Protection,2015,42(1):9-12.
[9]李宏艳,康立军,徐子杰,等.不同冲击倾向煤体失稳破坏声发射先兆信息分析[J].煤炭学报,2014,39(2):384-388.LI Hongyan,KANG Lijun,XU Zijie,et al.Precursor information analysis on acoustic emission of coal with different outburst proneness[J]. Journal of China Coal Society,2014,39(2):384-388.
[10]孙吉主,周健,唐春安.影响岩石声发射的几个因素[J].地壳形变与地震,1997,17(2):3-7.SUN Jizhu,ZHOU Jian,TANG Chunan. Factors affecting acoustic emission of rock[J].Crustal Deformation&Earthquake,1997,17(2):3-7.
[11]苏承东,郭保华,唐旭.漳村煤矿两种尺度煤样单轴压缩声发射特征的试验研究[J].煤炭学报,2013,38(S1):12-18.SU Chengdong,GUO Baohua,TANG Xu. Research on acoustic emission characteristics of Zhangcun coal samples in two sizes subject to uniaxial compression[J]. Journal of China Coal Society,2013,38(S1):12-18.
[12]高保彬,李回贵,李化敏,等.含水煤样破裂过程中的声发射及分形特性研究[J].采矿与安全工程学报,2015,32(4):665-670,676.GAO Baobin,LI Huigui,LI Huamin,et al. Acoustic emission and fractal characteristics of saturated coal samples in the failure process[J]. Journal of Mining&Safety Engineering,2015,32(4):665-670,676.
[13]许江,耿加波,彭守建,等.不同含水率条件下煤与瓦斯突出的声发射特性[J].煤炭学报,2015,40(5):1047-1054.XU Jiang,GENG Jiabo,PENG Shoujian,et al. Acoustic emission characteristics of coal and gas outburst under different moisture contents[J].Journal of China Coal Society,2015,40(5):1047-1054.
[14]刘刚,肖福坤,秦涛,等.循环载荷下煤样力学特性和损伤演化规律试验研究[J].煤炭科学技术, 2018, 46(2):131-137.LIU Gang,XIAO Fukun,QIN Tao,et al. Experimental study on mechanical characteristics and damage evolution law of coal samples under cyclic load[J].Coal Science and Technology,2018,46(2):131-137.
[15]赵洪宝,尹光志,李华华,等.含瓦斯突出煤声发射特性及其围压效应分析[J].重庆大学学报,2013,30(11):101-107.ZHAO Hongbao,YIN Guangzhi,LI Huahua,et al.Analysis on AE characteristic and it’s confining pressure effect of outburst coal containing gas[J]. Journal of Chongqing University,2013,30(11):101-107.
[16]曹安业,井广成,窦林名,等.不同加载速率下岩样损伤演化的声发射特征研究[J].采矿与安全工程学报,2015,32(6):923-928,935.CAO Anye,JING Guangcheng,DOU Linming,et al. Damage evolution law based on acoustic emission of sandy mudstone under different uniaxial loading rate[J].Journal of Mining&Safety Engineering,2015,32(6):923-928,935.
[17]赵振龙,赵坤,王晓.不同加载速率下类煤岩力学特性及损伤演化规律研究[J].煤炭科学技术,2017,45(10):41-47.ZHAO Zhenlong,ZHAO Kun,WANG Xiao. Study on mechanical characteristics and damage evolution law of coal-rock-like under different loading rates[J].Coal Science and Technology,2017,45(10):41-47.
[18]俞缙,李宏,陈旭,等.砂岩卸围压变形过程中渗透特性与声发射试验研究[J].岩石力学与工程学报,2014,33(1):69-79.YU Jin,LI Hong,CHEN Xu,et al.Experimental study of permeability and acoustic emission characteristics of sandstone during processes of unloading confining pressure and deformation[J].Chinese Journal of Rock Mechanics and Engineering,2014,(1):69-79.
[19]蒋长宝,黄滚,黄启翔.含瓦斯煤多级式卸围压变形破坏及渗透率演化规律实验[J].煤炭学报,2011,35(12):2039-2042.JIANG Changbao,HUANG Gun,HUANG Qixiang. Experiment on deformation failure and permeability evolution law of gas-containing coal under multi-stage unloading confining pressure[J].Journal of China Coal Society,2011,35(12):2039-2042.
[20]邱士利,冯夏庭,张传庆,等.不同卸围压速率下深埋大理岩卸荷力学特性试验研究[J].岩石力学与工程学报,2010,29(9):1807-1817.QIU Shili,FENG Xiating,ZHANG Chuanqing,et al.Experimental research on mechanical properties of deep-buried marble under different unloading rates of confining pressures[J]. Chinese Journal of Rock Mechanics and Engineering,2010,29(9):1807-1817.
[2]潘一山.煤与瓦斯突出、冲击地压复合动力灾害一体化研究[J].煤炭学报,2016,41(1):105-112.PAN Yishan. Integrated study on compound dynamic disaster of coal-gas outburst and rockburst[J].Journal of China Coal Society,2016,41(1):105-112.
[3]杨慧明.深部应力型突出灾害的声发射监测工艺及预警试验研究[J].煤矿安全,2017,48(2):17-20.YANG Huiming. Experimental study on acoustic emission monitoring technique and pre-warning of stress type outburst disasters in deep mine[J].Safety in Coal Mines,2017,48(2):17-20.
[4]吕贵春,邹银辉,李建功,等.基于AE传播规律监测急倾煤层掘进期动力现象[J].煤炭科学技术,2010,38(5):62-65.LYU Guichun,ZOU Yinhui,LI Jiangong,et al. Monitoring and measuring dynamic phenomenon of gateway driving in steep inclined seam based on AE transmission law[J].Coal Science and Technology,2010,38(5):62-65.
[5] MOGI K.Study of Elastic Shocks Caused by the Fracture of Heterogeneous Materials and its Relations to Earthquake Phenomena[J].Bull Earthq Res Inst,1962,40(1):125-173.
[6]张茹,谢和平,刘建锋,等.单轴多级加载岩石破坏声发射特性试验研究[J].岩石力学与工程学报,2006,25(12):2584-2588.ZHANG Ru,XIE Heping,LIU Jianfeng et al.Experimental study on acoustic emission characteristics of rock failure under uniaxial multilevel loadings[J].Chinese Journal of Rock Mechanics and Engineering,2006,25(12):2584-2588.
[7]曹树刚,刘延保,张立强.突出煤体变形破坏声发射特征的综合分析[J].岩石力学与工程学报,2007,26(S1):2794-2799.CAO Shugang,LIU Yanbao,ZHANG Liqiang.Study on characteristics of acoustic emission in outburst coal[J]. Chinese Journal of Rock Mechanics and Engineering,2007,26(S1):2794-2799.
[8]杨慧明.塑性煤与脆性煤破坏过程的声发射演化特征试验研究[J].矿业安全与环保,2015,42(1):9-12.YANG Huiming.Test study on acoustic emission evolution characteristics in failure process of plastic and brittle coal[J]. Mining Safety&Environmental Protection,2015,42(1):9-12.
[9]李宏艳,康立军,徐子杰,等.不同冲击倾向煤体失稳破坏声发射先兆信息分析[J].煤炭学报,2014,39(2):384-388.LI Hongyan,KANG Lijun,XU Zijie,et al.Precursor information analysis on acoustic emission of coal with different outburst proneness[J]. Journal of China Coal Society,2014,39(2):384-388.
[10]孙吉主,周健,唐春安.影响岩石声发射的几个因素[J].地壳形变与地震,1997,17(2):3-7.SUN Jizhu,ZHOU Jian,TANG Chunan. Factors affecting acoustic emission of rock[J].Crustal Deformation&Earthquake,1997,17(2):3-7.
[11]苏承东,郭保华,唐旭.漳村煤矿两种尺度煤样单轴压缩声发射特征的试验研究[J].煤炭学报,2013,38(S1):12-18.SU Chengdong,GUO Baohua,TANG Xu. Research on acoustic emission characteristics of Zhangcun coal samples in two sizes subject to uniaxial compression[J]. Journal of China Coal Society,2013,38(S1):12-18.
[12]高保彬,李回贵,李化敏,等.含水煤样破裂过程中的声发射及分形特性研究[J].采矿与安全工程学报,2015,32(4):665-670,676.GAO Baobin,LI Huigui,LI Huamin,et al. Acoustic emission and fractal characteristics of saturated coal samples in the failure process[J]. Journal of Mining&Safety Engineering,2015,32(4):665-670,676.
[13]许江,耿加波,彭守建,等.不同含水率条件下煤与瓦斯突出的声发射特性[J].煤炭学报,2015,40(5):1047-1054.XU Jiang,GENG Jiabo,PENG Shoujian,et al. Acoustic emission characteristics of coal and gas outburst under different moisture contents[J].Journal of China Coal Society,2015,40(5):1047-1054.
[14]刘刚,肖福坤,秦涛,等.循环载荷下煤样力学特性和损伤演化规律试验研究[J].煤炭科学技术, 2018, 46(2):131-137.LIU Gang,XIAO Fukun,QIN Tao,et al. Experimental study on mechanical characteristics and damage evolution law of coal samples under cyclic load[J].Coal Science and Technology,2018,46(2):131-137.
[15]赵洪宝,尹光志,李华华,等.含瓦斯突出煤声发射特性及其围压效应分析[J].重庆大学学报,2013,30(11):101-107.ZHAO Hongbao,YIN Guangzhi,LI Huahua,et al.Analysis on AE characteristic and it’s confining pressure effect of outburst coal containing gas[J]. Journal of Chongqing University,2013,30(11):101-107.
[16]曹安业,井广成,窦林名,等.不同加载速率下岩样损伤演化的声发射特征研究[J].采矿与安全工程学报,2015,32(6):923-928,935.CAO Anye,JING Guangcheng,DOU Linming,et al. Damage evolution law based on acoustic emission of sandy mudstone under different uniaxial loading rate[J].Journal of Mining&Safety Engineering,2015,32(6):923-928,935.
[17]赵振龙,赵坤,王晓.不同加载速率下类煤岩力学特性及损伤演化规律研究[J].煤炭科学技术,2017,45(10):41-47.ZHAO Zhenlong,ZHAO Kun,WANG Xiao. Study on mechanical characteristics and damage evolution law of coal-rock-like under different loading rates[J].Coal Science and Technology,2017,45(10):41-47.
[18]俞缙,李宏,陈旭,等.砂岩卸围压变形过程中渗透特性与声发射试验研究[J].岩石力学与工程学报,2014,33(1):69-79.YU Jin,LI Hong,CHEN Xu,et al.Experimental study of permeability and acoustic emission characteristics of sandstone during processes of unloading confining pressure and deformation[J].Chinese Journal of Rock Mechanics and Engineering,2014,(1):69-79.
[19]蒋长宝,黄滚,黄启翔.含瓦斯煤多级式卸围压变形破坏及渗透率演化规律实验[J].煤炭学报,2011,35(12):2039-2042.JIANG Changbao,HUANG Gun,HUANG Qixiang. Experiment on deformation failure and permeability evolution law of gas-containing coal under multi-stage unloading confining pressure[J].Journal of China Coal Society,2011,35(12):2039-2042.
[20]邱士利,冯夏庭,张传庆,等.不同卸围压速率下深埋大理岩卸荷力学特性试验研究[J].岩石力学与工程学报,2010,29(9):1807-1817.QIU Shili,FENG Xiating,ZHANG Chuanqing,et al.Experimental research on mechanical properties of deep-buried marble under different unloading rates of confining pressures[J]. Chinese Journal of Rock Mechanics and Engineering,2010,29(9):1807-1817.