真三轴应力条件下钻孔围岩稳定性及塑性区特性
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摘要
为探究中间主应力对预制孔岩石力学性质的影响,基于自主研发的"多功能真三轴流固耦合试验系统",进行了等b等σ3试验。试验结果表明:主应力方向、中间主应力对岩石变形和强度特性均有较大影响。裂纹特征应力值随中主应力系数b的增加呈现先增大后减小的趋势;裂纹主要在垂直孔轴线方向发育并首先在较小的主应力方向发生破坏。几种条件下试样的强度均随中主应力系数的增大而先增大后减小。其中,最大主应力平行于孔轴线时强度最高,稳定性最好;在中主应力系数b较小时,中间主应力平行于孔轴线时强度最低,而b较大时孔轴线沿最小主应力时强度最低。基于广义平面应变理论,分析了中间主应力对孔周围塑性区的影响。
In order to explore the influence of intermediate principal stress on the mechanical properties of prefabricated holes in rock,the authors carried out the constant b and σ_3 tests of prefabricated hole in sandstone under true triaxial stress conditions based on the self-developed"multi-functional true triaxial geophysical( TTG) apparatus".The experimental results show that the principal stress axis direction and the intermediate principal stress all have great influence on the deformation and strength characteristics of the rock.The crack characteristic stress increases first and then decrease with the increase of the principal stress coefficient b.In addition,the crack develops mainly in the direction of the vertical borehole axis and begins to destroy in the direction of the smaller principal stress.The strength of the specimen increases first and then decreases with the increase of the principal stress coefficient in several test conditions.Among them,the highest strength and the best stability occur when the maximum principal stress is parallel to the borehole axis.The rock strength is the lowest when the intermediate principal stress is parallel to the borehole axis at a smaller value of b.In contrast,the strength is the lowest when the minimum principal stress is parallel to the borehole axis at a larger value of b.Furthermore,the authors analyzed the effects of intermediate principal stress on the plasticzone around the hole based on the generalized plane strain theory.
In order to explore the influence of intermediate principal stress on the mechanical properties of prefabricated holes in rock,the authors carried out the constant b and σ_3 tests of prefabricated hole in sandstone under true triaxial stress conditions based on the self-developed"multi-functional true triaxial geophysical( TTG) apparatus".The experimental results show that the principal stress axis direction and the intermediate principal stress all have great influence on the deformation and strength characteristics of the rock.The crack characteristic stress increases first and then decrease with the increase of the principal stress coefficient b.In addition,the crack develops mainly in the direction of the vertical borehole axis and begins to destroy in the direction of the smaller principal stress.The strength of the specimen increases first and then decreases with the increase of the principal stress coefficient in several test conditions.Among them,the highest strength and the best stability occur when the maximum principal stress is parallel to the borehole axis.The rock strength is the lowest when the intermediate principal stress is parallel to the borehole axis at a smaller value of b.In contrast,the strength is the lowest when the minimum principal stress is parallel to the borehole axis at a larger value of b.Furthermore,the authors analyzed the effects of intermediate principal stress on the plasticzone around the hole based on the generalized plane strain theory.
引文
[1]马念杰.回采巷道围岩活动规律及其控制[D].徐州:中国矿业大学,1988.MA Nianjie.The activity rule and control of surrounding rock in mining roadway[D].Xuzhou:China University of Mining&Technology,1988.
[2]郭晓菲,马念杰,赵希栋,等.圆形巷道围岩塑性区的一般形态及其判定准则[J].煤炭学报,2016,41(8):1872-1877.GUO Xiaofei,MA Nianjie,ZHAO Xidong,et al.General shapes and criterion for surrounding rock mass plastic zone of round roadway[J].Journal of China Coal Society,2016,41(8):1872-1877.
[3]HICKMAN SH,ZOBCK MD.Stress orientations and magnitudes in the SAFOD pilot hole.Geophys Res Lett 31,2004:L15S12.
[4]LEE H,MOON T,HAIMSON B C.Borehole breakouts induced in Arkosic sandstones and a discrete element analysis[J].Rock Mech Rock Eng,2016,49:1369-1388.
[5]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,1994,19(1):20-31.DONG Fangting,SONG Hongwei,GUO Zhihong,et al.Theory of roadway surrounding rock loose circle support[J].Journal of China Coal Society,1994,19(1):20-31.
[6]马念杰,李季,赵志强.圆形巷道围岩偏应力场及塑性区分布规律研究[J].中国矿业大学学报,2015,44(2):206-213.MA Nianjie,LI Ji,ZHAO Zhiqiang.Distribution of the deviatoric stress field and plastic zone in circular roadway surrounding rock[J].Journal of China University of Mining&Technology,2015,44(2):206-213.
[7]陈立伟,彭建兵,范文,等.基于统一强度理论的非均匀应力场圆形巷道围岩塑性区分析[J].煤炭学报,2007,32(1):20-23.CHEN Liwei,PENG Jianbing,FAN Wen,et al.Analysis based on unified strength theory of non-uniform stress field circular roadway for plastic zone[J].Journal of China Coal Society,2007,32(1):20-23.
[8]韩观胜,靖洪文,苏海健,等.预制双圆形钻孔砂岩强度与变形破坏特征[J].煤炭学报,2017,42(4):871-878.HAN Guansheng,JING Hongwen,SU Haijian,et al.Experimental study on compressive strength and fracture characteristics of sandstone containing double circular cavities[J].Journal of China Coal Society,2017,42(4):871-878.
[9]赵洪宝,胡桂林,王飞虎.等.局部荷载下含中心钻孔煤体裂纹扩展特征量化分析[J].煤炭学报,2017,42(4):860-870.ZHAO Hongbao,HU Guilin,WANG Feihu,et al.Quantitative analysis of crack expansion in specimens of coal having a single pre-existing hole[J].Journal of China Coal Society,2017,42(4):860-870.
[10]李术才,王汉鹏,钱七虎,等.深部巷道围岩分区破裂化现象现场监测研究[J].岩石力学与工程学报,2008,27(8):1545-1553.LI Shucai,WANG Hanpeng,QIAN Qihu,et al.In-situ monitoring research on zonal disintegration of surrounding rock mass in deep mine roadways[J].Chinese Journal of Rock Mechanics and Engineering,2008,27(8):1545-1553.
[11]常聚才,谢广祥.深部巷道围岩力学特征及其稳定性控制[J].煤炭学报,2009,34(7):881-886.CHANG Jucai,XIE Guangxiang.Mechanical characteristics and stability control of rock roadway Surrounding rock in deep mine[J].Journal of China Coal Society,2009,34(7):881-886.
[12]周辉,渠成堃,王竹春,等.深井巷道掘进围岩演化特征模拟与扰动应力场分析[J].岩石力学与工程学报,2017,36(8):1821-1831.ZHOU Hui,QU Chengkan,WANG Zhuchun,et al.Simulating the variation of surrounding rock and analyzing the disturbed stress field during excavation of deep mine roadway[J].Chinese Journal of Rock Mechanics and Engineering,2017,36(8):1821-1831.
[13]马念杰,李季,赵希栋,等.深部煤与瓦斯共采中的优质瓦斯通道及其构建方法[J].煤炭学报,2015,40(4):742-748.MA Nianjie,LI Ji,ZHAO Xidong,et al.High quality gas channel and its construction method applied to coal and gas simultaneous extraction in deep mining[J].Journal of China Coal Society,2015,40(4):742-748.
[14]李春睿,康立军,齐庆新,等.深部巷道围岩分区破裂与冲击地压关系初探[J].煤炭学报,2010,35(2):185-189.LI Chunrui,KANG Lijun,QI Qingxin,et al.Probe into relationship between zonal fracturing and rock burst in deep tunnel[J].Journal of China Coal Society,2010,35(2):185-189.
[15]翟成,李全贵,孙臣,等.松软煤层水力压裂钻孔失稳分析及固化成孔方法[J].煤炭学报,2012,37(9):1431-1436.ZHAI Cheng,LI Quangui,SUN Chen,et al.Analysis on borehole instability and control method of pore-forming of hydraulic fracturing in soft coal seam[J].Journal of China Coal Society,2012,37(9):1431-1436.
[16]潘阳,赵光明,孟祥瑞.非均匀应力场下巷道围岩弹塑性分析[J].煤炭学报,2011,36(S1):53-57.PAN Yang,ZHAO Guangming,MENG Xiangrui.Elasto-plastic analysis on surrounding rock mass under non-uniform stress field[J].Journal of China Coal Society,2011,36(S1):53-57.
[17]张强,王水林,葛修润.圆形巷道围岩应变软化弹塑性分析[J].岩石力学与工程学报,2010,29(5):1031-1035.ZHANG Qiang,WANG Shuilin,GE Xiurun.Elastoplastic analysis of circular openings in strain-softening rock masses[J].Chinese Journal of Rock Mechanics and Engineering,2010,29(5):1031-1035.
[18]HAIMSON B,CHANG C.A new true triaxial cell for testing mechanical properties of rock and its use to determine rock strength and deformability of westerly granite[J].International Journal of Rock Mechanics&Mining Sciences,2000,37(1-2):285-296.
[19]FENG X T,ZHANG X W,KONG R,et al.A novel mogi type true triaxial testing apparatus and its use to obtain complete stressstrain curves of hard rocks[J].Rock Mechanics&Rock Engineering,2016,49(5):1649-1662.
[20]尹光志,鲁俊,李星,等.中间主应力对砂岩扩容及强度特性影[J].煤炭学报,2017,42(4):879-885.YIN Guangzhi,LU Jun,LI Xing,et al.Influence of intermediate principal stress on dilation and strength characteristics of sandstone[J].Journal of China Coal Society,2017,42(4):879-885.
[21]尹光志,鲁俊,李星,等.应力Lode角对砂岩变形特性影响[J].岩石力学与工程学报,2017,36(9):2081-2091.YIN Guangzhi,LU Jun,LI Xing,et al.Influence of stress Lode angle on deformation characteristics of sandstone[J].Chinese Journal of Rock Mechanics and Engineering,2017,36(9):2081-2091
[22]尹光志,李星,鲁俊,等.真三轴应力条件下层状复合岩石破坏准则[J].岩石力学与工程学报,2017,36(2):261-269.YIN Guangzhi,LI Xing,LU Jun,et al.A failure criterion for layered composite rock under true triaxial stress conditions[J].Chinese Journal of Rock Mechanics and Engineering,2017,36(2):261-269.
[23]尹光志,李铭辉,许江,等.多功能真三轴流固耦合试验系统的研制与应用[J].岩石力学与工程学报,2015,34(12):2436-2445.YIN Guangzhi,LI Minghui,XU Jiang,et al.A new multifunctional true triaxial fluid solid coupling experiment system and its applications[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(12):2436-2445.
[24]周辉,孟凡震,张传庆,等.硬岩应力-应变门槛值特点及产生机制[J].岩石力学与工程学报,2015,34(8):1513-1521.ZHOU Hui,MENG Fanzhen,ZHANG Chuangqing,et al.Characteristics and mechanism of occurrence of stress thresholds and corresponding strain for hard rock[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(8):1513-1521.
[25]高峰.应力分布规律及其对巷道围岩稳定性影响研究[D].徐州:中国矿业大学,2009.GAO feng.Resarch on ground stress distribution characteristics and its effect on roadway surrounding rock stability[D].Xuzhou:China University of Mining&Technology,2009.
[26]郑雨天.井巷和钻孔周围三维应力场的简化模式[J].煤炭学报,1982(4):74-80.ZHENG Yutian.A simplified model of triaxial stress field around long openings[J].Journal of China Coal Society,1982(4):74-80.
[2]郭晓菲,马念杰,赵希栋,等.圆形巷道围岩塑性区的一般形态及其判定准则[J].煤炭学报,2016,41(8):1872-1877.GUO Xiaofei,MA Nianjie,ZHAO Xidong,et al.General shapes and criterion for surrounding rock mass plastic zone of round roadway[J].Journal of China Coal Society,2016,41(8):1872-1877.
[3]HICKMAN SH,ZOBCK MD.Stress orientations and magnitudes in the SAFOD pilot hole.Geophys Res Lett 31,2004:L15S12.
[4]LEE H,MOON T,HAIMSON B C.Borehole breakouts induced in Arkosic sandstones and a discrete element analysis[J].Rock Mech Rock Eng,2016,49:1369-1388.
[5]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,1994,19(1):20-31.DONG Fangting,SONG Hongwei,GUO Zhihong,et al.Theory of roadway surrounding rock loose circle support[J].Journal of China Coal Society,1994,19(1):20-31.
[6]马念杰,李季,赵志强.圆形巷道围岩偏应力场及塑性区分布规律研究[J].中国矿业大学学报,2015,44(2):206-213.MA Nianjie,LI Ji,ZHAO Zhiqiang.Distribution of the deviatoric stress field and plastic zone in circular roadway surrounding rock[J].Journal of China University of Mining&Technology,2015,44(2):206-213.
[7]陈立伟,彭建兵,范文,等.基于统一强度理论的非均匀应力场圆形巷道围岩塑性区分析[J].煤炭学报,2007,32(1):20-23.CHEN Liwei,PENG Jianbing,FAN Wen,et al.Analysis based on unified strength theory of non-uniform stress field circular roadway for plastic zone[J].Journal of China Coal Society,2007,32(1):20-23.
[8]韩观胜,靖洪文,苏海健,等.预制双圆形钻孔砂岩强度与变形破坏特征[J].煤炭学报,2017,42(4):871-878.HAN Guansheng,JING Hongwen,SU Haijian,et al.Experimental study on compressive strength and fracture characteristics of sandstone containing double circular cavities[J].Journal of China Coal Society,2017,42(4):871-878.
[9]赵洪宝,胡桂林,王飞虎.等.局部荷载下含中心钻孔煤体裂纹扩展特征量化分析[J].煤炭学报,2017,42(4):860-870.ZHAO Hongbao,HU Guilin,WANG Feihu,et al.Quantitative analysis of crack expansion in specimens of coal having a single pre-existing hole[J].Journal of China Coal Society,2017,42(4):860-870.
[10]李术才,王汉鹏,钱七虎,等.深部巷道围岩分区破裂化现象现场监测研究[J].岩石力学与工程学报,2008,27(8):1545-1553.LI Shucai,WANG Hanpeng,QIAN Qihu,et al.In-situ monitoring research on zonal disintegration of surrounding rock mass in deep mine roadways[J].Chinese Journal of Rock Mechanics and Engineering,2008,27(8):1545-1553.
[11]常聚才,谢广祥.深部巷道围岩力学特征及其稳定性控制[J].煤炭学报,2009,34(7):881-886.CHANG Jucai,XIE Guangxiang.Mechanical characteristics and stability control of rock roadway Surrounding rock in deep mine[J].Journal of China Coal Society,2009,34(7):881-886.
[12]周辉,渠成堃,王竹春,等.深井巷道掘进围岩演化特征模拟与扰动应力场分析[J].岩石力学与工程学报,2017,36(8):1821-1831.ZHOU Hui,QU Chengkan,WANG Zhuchun,et al.Simulating the variation of surrounding rock and analyzing the disturbed stress field during excavation of deep mine roadway[J].Chinese Journal of Rock Mechanics and Engineering,2017,36(8):1821-1831.
[13]马念杰,李季,赵希栋,等.深部煤与瓦斯共采中的优质瓦斯通道及其构建方法[J].煤炭学报,2015,40(4):742-748.MA Nianjie,LI Ji,ZHAO Xidong,et al.High quality gas channel and its construction method applied to coal and gas simultaneous extraction in deep mining[J].Journal of China Coal Society,2015,40(4):742-748.
[14]李春睿,康立军,齐庆新,等.深部巷道围岩分区破裂与冲击地压关系初探[J].煤炭学报,2010,35(2):185-189.LI Chunrui,KANG Lijun,QI Qingxin,et al.Probe into relationship between zonal fracturing and rock burst in deep tunnel[J].Journal of China Coal Society,2010,35(2):185-189.
[15]翟成,李全贵,孙臣,等.松软煤层水力压裂钻孔失稳分析及固化成孔方法[J].煤炭学报,2012,37(9):1431-1436.ZHAI Cheng,LI Quangui,SUN Chen,et al.Analysis on borehole instability and control method of pore-forming of hydraulic fracturing in soft coal seam[J].Journal of China Coal Society,2012,37(9):1431-1436.
[16]潘阳,赵光明,孟祥瑞.非均匀应力场下巷道围岩弹塑性分析[J].煤炭学报,2011,36(S1):53-57.PAN Yang,ZHAO Guangming,MENG Xiangrui.Elasto-plastic analysis on surrounding rock mass under non-uniform stress field[J].Journal of China Coal Society,2011,36(S1):53-57.
[17]张强,王水林,葛修润.圆形巷道围岩应变软化弹塑性分析[J].岩石力学与工程学报,2010,29(5):1031-1035.ZHANG Qiang,WANG Shuilin,GE Xiurun.Elastoplastic analysis of circular openings in strain-softening rock masses[J].Chinese Journal of Rock Mechanics and Engineering,2010,29(5):1031-1035.
[18]HAIMSON B,CHANG C.A new true triaxial cell for testing mechanical properties of rock and its use to determine rock strength and deformability of westerly granite[J].International Journal of Rock Mechanics&Mining Sciences,2000,37(1-2):285-296.
[19]FENG X T,ZHANG X W,KONG R,et al.A novel mogi type true triaxial testing apparatus and its use to obtain complete stressstrain curves of hard rocks[J].Rock Mechanics&Rock Engineering,2016,49(5):1649-1662.
[20]尹光志,鲁俊,李星,等.中间主应力对砂岩扩容及强度特性影[J].煤炭学报,2017,42(4):879-885.YIN Guangzhi,LU Jun,LI Xing,et al.Influence of intermediate principal stress on dilation and strength characteristics of sandstone[J].Journal of China Coal Society,2017,42(4):879-885.
[21]尹光志,鲁俊,李星,等.应力Lode角对砂岩变形特性影响[J].岩石力学与工程学报,2017,36(9):2081-2091.YIN Guangzhi,LU Jun,LI Xing,et al.Influence of stress Lode angle on deformation characteristics of sandstone[J].Chinese Journal of Rock Mechanics and Engineering,2017,36(9):2081-2091
[22]尹光志,李星,鲁俊,等.真三轴应力条件下层状复合岩石破坏准则[J].岩石力学与工程学报,2017,36(2):261-269.YIN Guangzhi,LI Xing,LU Jun,et al.A failure criterion for layered composite rock under true triaxial stress conditions[J].Chinese Journal of Rock Mechanics and Engineering,2017,36(2):261-269.
[23]尹光志,李铭辉,许江,等.多功能真三轴流固耦合试验系统的研制与应用[J].岩石力学与工程学报,2015,34(12):2436-2445.YIN Guangzhi,LI Minghui,XU Jiang,et al.A new multifunctional true triaxial fluid solid coupling experiment system and its applications[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(12):2436-2445.
[24]周辉,孟凡震,张传庆,等.硬岩应力-应变门槛值特点及产生机制[J].岩石力学与工程学报,2015,34(8):1513-1521.ZHOU Hui,MENG Fanzhen,ZHANG Chuangqing,et al.Characteristics and mechanism of occurrence of stress thresholds and corresponding strain for hard rock[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(8):1513-1521.
[25]高峰.应力分布规律及其对巷道围岩稳定性影响研究[D].徐州:中国矿业大学,2009.GAO feng.Resarch on ground stress distribution characteristics and its effect on roadway surrounding rock stability[D].Xuzhou:China University of Mining&Technology,2009.
[26]郑雨天.井巷和钻孔周围三维应力场的简化模式[J].煤炭学报,1982(4):74-80.ZHENG Yutian.A simplified model of triaxial stress field around long openings[J].Journal of China Coal Society,1982(4):74-80.