峰前卸荷损伤大理岩的动静力学特性试验研究
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摘要
深部巷(隧)道开挖将导致围岩卸荷损伤甚至破裂,这类损伤破裂围岩还将承受后继采掘活动带来的静态扰动和动力冲击,继续破裂甚至破坏失稳,因此,有必要开展损伤破裂围岩再承载力学行为的研究。首先开展3级围压(15,25,35 MPa)条件下的大理岩峰前卸荷试验,每级围压分4个卸荷点,共制备72个损伤破裂岩样;然后,分别采用MTS815试验机和分离式Hopkinson压杆对损伤岩样进行静、动态单轴压缩破坏试验。试验结果表明:相同围压(或卸荷点)下,岩样卸荷损伤变量与卸荷点(或围压)呈正相关关系;卸荷损伤岩样的静、动态宏观力学参数均随损伤变量的增加而呈负指数函数衰减,且脆性破坏特征趋于不明显。损伤变量小于其临界值Dc=0.17时,动态增强因子稳定在1.5左右,动弹性模量快速下降而静弹性模量变化不显著;损伤变量大于Dc时,动态增强因子急剧增大,而动、静态弹性模量则趋于一致。这种动静态的差异性是卸荷损伤效应和应变率效应复杂的耦合作用导致的。研究结论对深部巷(隧)道围岩力学参数的选取和支护方案的优化有一定借鉴意义。
Excavation of tunnels under deep high stress environment will induce unloading damage or even cracking of surrounding rock and,then,the damaged surrounding rock will rupture or fail under static and dynamic loads caused by mining activities. Therefore,it is necessary to study the dynamic and static mechanical behavior of damaged surrounding rock. Pre-peak unloading tests on 72 damaged marble specimens were performed under three confining pressures of 15,25 and 35 MPa with four unloading points respectively corresponding to 70%,80%,90% and 100% of each confining pressure,and then,static and dynamic uniaxial compression tests of the damaged samples were respectively carried out by MTS815 and split Hopkinson pressure bar(SHPB) test system. The test results show that the damage variable of the rock samples increases with increasing the unloading point/confining pressure under the same confining pressure/unloading point. The static and dynamic compressive strength and elastic modulus of the unloading damaged rock samples decrease with the damage variable in a negative exponential function. When the damage variable is lower than the critical value Dc = 0.17,the dynamic enhancement factor keeps stable around 1.5. The dynamic elastic modulus decreases rapidly while the static elastic modulus does not change significantly. When the damage variable is greater than 0.17,the dynamic enhancement factor increases sharply while the dynamic and static elastic moduli tend to be the same. The dynamic and static differences are attributed to the complex coupling of unloading damage effect and strain rate effect. The findings of this research can provide a reference for the selection of the mechanical parameters of the surrounding rock and the optimization of the support scheme.
Excavation of tunnels under deep high stress environment will induce unloading damage or even cracking of surrounding rock and,then,the damaged surrounding rock will rupture or fail under static and dynamic loads caused by mining activities. Therefore,it is necessary to study the dynamic and static mechanical behavior of damaged surrounding rock. Pre-peak unloading tests on 72 damaged marble specimens were performed under three confining pressures of 15,25 and 35 MPa with four unloading points respectively corresponding to 70%,80%,90% and 100% of each confining pressure,and then,static and dynamic uniaxial compression tests of the damaged samples were respectively carried out by MTS815 and split Hopkinson pressure bar(SHPB) test system. The test results show that the damage variable of the rock samples increases with increasing the unloading point/confining pressure under the same confining pressure/unloading point. The static and dynamic compressive strength and elastic modulus of the unloading damaged rock samples decrease with the damage variable in a negative exponential function. When the damage variable is lower than the critical value Dc = 0.17,the dynamic enhancement factor keeps stable around 1.5. The dynamic elastic modulus decreases rapidly while the static elastic modulus does not change significantly. When the damage variable is greater than 0.17,the dynamic enhancement factor increases sharply while the dynamic and static elastic moduli tend to be the same. The dynamic and static differences are attributed to the complex coupling of unloading damage effect and strain rate effect. The findings of this research can provide a reference for the selection of the mechanical parameters of the surrounding rock and the optimization of the support scheme.
引文
[1]何满潮,谢和平,彭苏萍,等.深部开采岩体力学研究[J].岩石力学与工程学报,2005,24(16):2 803-2 813.(HE Manchao,XIEHeping,PENG Suping,et al.Study on rock mechanics in deep mining engineering[J].Chinese Journal of Rock Mechanics and Engineering,2005,24(16):2 803-2 813.(in Chinese))
[2]张春生,陈祥荣,侯靖,等.锦屏二级水电站深埋大理岩力学特性研究[J].岩石力学与工程学报,2010,29(10):1 999-2 009.(ZHANG Chunsheng,CHEN Xiangrong,HOU Jing,et al.Study of mechanical behavior of deep-buried marble at JINPING II hydropower station[J].Chinese Journal of Rock Mechanics and Engineering,2010,29(10):1 999-2 009.(in Chinese))
[3]宁宇.大采高综采煤壁片帮冒顶机理与控制技术[J].煤炭学报,2009,34(1):50-52.(NING Yu.Mechanism and control technique of the rib spalling in fully mechanized mining face with great mining height[J].Journal of China Coal Society,2009,34(1):50-52.(in Chinese))
[4]朱维申,杨为民,项吕,等.大型洞室边墙松弛劈裂区的室内和现场研究及反馈分析[J].岩石力学与工程学报,2011,30(7):1 310-1 317.(ZHU Weishen,YANG Weimin,XIANG Lu,et al.Laboratory and filed study of splitting failure on side wall of large-scale cavern and feedback analysis[J].Chinese Journal of Rock Mechanics and Engineering,2011,30(7):1 310-1 317.(in Chinese))
[5]潘一山,李忠华,章梦涛.我国冲击地压分布、类型、机理及防治研究[J].岩石力学与工程学报,2003,22(11):1 844-1 851.(PANYishan,LI Zhonghua,ZHANG Mengtao.Distribution,type,mechanism and prevention of rockbrust in China[J].Chinese Journal of Rock Mechanics and Engineering,2003,22(11):1 844-1 851.(in Chinese))
[6]尤明庆,华安增.岩石岩样的三轴卸围压试验[J].岩石力学与工程学报,1998,17(1):24-29.(YOU Mingqing,HUA Anzeng.Triaxial confining depressure test of rock sample[J].Chinese Journal of Rock Mechanics and Engineering,1998,17(1):24-29.(in Chinese))
[7]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):1 807-1 817.(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):1 807-1 817.(in Chinese))
[8]周科平,胡振襄,李杰林,等.基于核磁共振技术的大理岩卸荷损伤演化规律研究[J].岩石力学与工程学报,2014,33(增2):3 523-3 530.(ZHOU Keping,HU Zhenxiang,LI Jielin,et al.Study of marble damage evolution laws under unloading condition based on nuclear magnetic resonance technique[J].Chinese Journal of Rock Mechanics and Engineering,2014,33(Supp.2):3 523-3 530.(in Chinese))
[9]CAI M,KAISER P K,TASAKA Y,et al.Generalized crack initiation and crack damage stress thresholds of brittle rock masses near underground excavations[J].International Journal of Rock Mechanics and Mining Sciences,2004,41(5):833-847.
[10]张黎明,王在泉,宋全锋,等.粉砂岩卸荷破坏全过程的试验研究[J].岩石力学与工程学报,2005,24(增1):5 043-5 047.(ZHANGLiming,WANG Zaiquan,SONG Quanfeng,et al.Experimental study on the total failure course of silt sand under unloading condition[J].Chinese Journal of Rock Mechanics and Engineering,2005,24(Supp.1):5 043-5 047.(in Chinese))
[11]任建喜,葛修润,蒲毅彬,等.岩石卸荷损伤演化机制CT实时分析初探[J].岩石力学与工程学报,2000,19(6):697-701.(RENJianxi,GE Xiurun,PU Yibin,et al.Primary study of real-time CT testing of unloading damage evolution law of rock[J].Chinese Journal of Rock Mechanics and Engineering,2000,19(6):697-701.(in Chinese))
[12]李天斌,王兰生.卸荷应力状态下玄武岩变形破坏特征的试验研究[J].岩石力学与工程学报,1993,12(4):321-327.(LI Tianbin,WANGLansheng.An experimental study on the deformation and failure features of a basalt under unloading condition[J].Chinese Journal of Rock Mechanics and Engineering,1993,12(4):321-327.(in Chinese))
[13]刘建,李建朋.砂岩高应力峰前卸围压试验研究[J].岩石力学与工程学报,2011,30(3):473-479.(LIU Jian,LI Jianpeng.Experimental research on sandstonepre-peak unloading process under high confining pressure[J].Chinese Journal of Rock Mechanics and Engineering,2011,30(3):473-479.(in Chinese))
[14]尹土兵,李夕兵,王斌,等.高温后砂岩动态压缩条件下力学特性研究[J].岩土工程学报,2011,33(5):777-784.(YIN Tubing,LI Xibing,WANG Bin,et al.Mechanical properties of sandstones after high temperature under dynamic loading[J].Chinese Journal of Geotechnical Engineering,2011,33(5):777-784.(in Chinese))
[15]吴安杰,邓建华,顾乡,等.冻融循环作用下泥质白云岩力学特性及损伤演化规律研究[J].岩土力学,2014,35(11):3 065-3 072.(WU Anjie,DENG Jianhua,GU Xiang,et al.Research on mechanical properties and damage evolution law of argillaceous dolomite under freeze-thaw cycles[J].Rock and Soil Mechnics,2014,35(11):3 065-3 072.(in Chinese))
[16]王伟,龚传根,朱鹏辉,等.大理岩干湿循环力学特性试验研究[J].水利学报,2017,48(10):1 175-1 184.(WANG Wei,GONGChuangen,ZHU Penghui,et al.Experimental study on mechanical properties of marble under hydraulic weathering coupling[J].Journal of Hydraulic Engineering,2017,48(10):1 175-1 184.(in Chinese))
[17]罗丹旎,苏国韶,何保煜.不同饱水度花岗岩的真三轴岩爆试验研究[J].岩土力学,2019,DOI:10.16285/j.rsm.2017.2432.(LUO Danni,SU Guoshao,HE Baoyu.True triaxial test on rockburst of granites with different water saturation[J].Rock and Soil Mechnics,2019,DOI:10.16285/j.rsm.2017.2432.(in Chinese))
[18]李光雷,蔚立元,苏海健,等.化学腐蚀灰岩SHPB冲击动力学性能研究[J].岩石力学与工程学报,2018,37(9):2 075-2 083.(LIGuanglei,YU Liyuan,SU Haijian,et al.Dynamic properties of corroded limestone based on SHPB[J].Chinese Journal of Rock Mechanics and Engineering,2018,37(9):2 075-2 083.(in Chinese))
[19]尤明庆,苏承东,李小双.损伤岩石岩样的力学特性与纵波速度关系研究[J].岩石力学与工程学报,2008,27(3):458-467.(YOUMingqing,SU Chengdong,LI Xiaoshuang.Study on relation between mechanical properties and longitudinal wave velocities for damaged rock samples[J].Chinese Journal of Rock Mechanics and Engineering,2008,27(3):458-467.(in Chinese))
[20]FREW D J,FORRESTAL M J,CHEN W.Pulse shaping techniques for testing brittle materials with a split Hopkinson pressure bar[J].Experimental Mechanics,2002,42(1):93-106.
[21]周子龙,李夕兵,岩小明.岩石SHPB测试中岩样恒应变率变形的加载条件[J].岩石力学与工程学报,2009,28(12):2 445-2 452.(ZHOU Zilong,LI Xibing,YAN Xiaoming.Loading condition for specimen deformation at constant stain rate in SHPB test of rock[J].Chinese Journal of Rock Mechanics and Engineering,2009,28(12):2 445-2 452.(in Chinese))
[22]蔚立元,李光雷,苏海健,等.高温后无烟煤静动态压缩力学特性研究[J].岩石力学与工程学报,2017,36(11):2 712-2 719.(YULiyuan,LI Guanglei,SU Haijian,et al.Experimental study on static and dynamic mechanical properties of anthracite after high temperature heating[J].Chinese Journal of Rock Mechanics and Engineering,201,36(11):2 712-2 719.(in Chinese))
[23]鞠杨,谢和平.基于应变等效性假说的损伤定义的适用条件[J].应用力学学报,1998,15(1):43-49.(JU Yang,XIE Heping.Avariable condition of the damage description based on hypothesis of strain equivalence[J].Chinese Journal of Applied Mechanics,1998,15(1):43-49.(in Chinese))
[24]MENG Q B,ZHANG M W,HAN L J,et al.Acoustic emission characteristics of red sandstone specimens under uniaxial cyclic loading and unloading compression[J].Rock Mechanics and Rock Engineering,2018,51(4):969-988.
[25]王礼立.应力波基础[M].北京:国防工业出版社,2005:52-60.(WANG Lili.Foundation of stress waves[M].Beijing:National Defense Industry Press,2005:52-60.(in Chinese))
[26]宫凤强,王进,李夕兵.岩石压缩特性的率效应与动态增强因子统一模型[J].岩石力学与工程学报,2018,37(7):1 586-1 595.(GONG Fengqiang,WANG Jin,LI Xibing.The rate effect of compression characteristics and a unified model of dynamic increasing factor for rock materials[J].Chinese Journal of Rock Mechanics and Engineering,2018,37(7):1 586-1 595.(in Chinese))
[27]谢和平,鞠杨,黎立云.基于能量耗散与释放原理的岩石强度与整体破坏准则[J].岩石力学与工程学报,2005,24(17):3 003-3 010.(XIE Heping,JU Yang,LI Liyun.Criteria for strength and structural failure of rocks based on energy dissipation and energy release principles[J].Chinese Journal of Rock Mechanics and Engineering,2005,24(17):3 003-3 010.(in Chinese))
[2]张春生,陈祥荣,侯靖,等.锦屏二级水电站深埋大理岩力学特性研究[J].岩石力学与工程学报,2010,29(10):1 999-2 009.(ZHANG Chunsheng,CHEN Xiangrong,HOU Jing,et al.Study of mechanical behavior of deep-buried marble at JINPING II hydropower station[J].Chinese Journal of Rock Mechanics and Engineering,2010,29(10):1 999-2 009.(in Chinese))
[3]宁宇.大采高综采煤壁片帮冒顶机理与控制技术[J].煤炭学报,2009,34(1):50-52.(NING Yu.Mechanism and control technique of the rib spalling in fully mechanized mining face with great mining height[J].Journal of China Coal Society,2009,34(1):50-52.(in Chinese))
[4]朱维申,杨为民,项吕,等.大型洞室边墙松弛劈裂区的室内和现场研究及反馈分析[J].岩石力学与工程学报,2011,30(7):1 310-1 317.(ZHU Weishen,YANG Weimin,XIANG Lu,et al.Laboratory and filed study of splitting failure on side wall of large-scale cavern and feedback analysis[J].Chinese Journal of Rock Mechanics and Engineering,2011,30(7):1 310-1 317.(in Chinese))
[5]潘一山,李忠华,章梦涛.我国冲击地压分布、类型、机理及防治研究[J].岩石力学与工程学报,2003,22(11):1 844-1 851.(PANYishan,LI Zhonghua,ZHANG Mengtao.Distribution,type,mechanism and prevention of rockbrust in China[J].Chinese Journal of Rock Mechanics and Engineering,2003,22(11):1 844-1 851.(in Chinese))
[6]尤明庆,华安增.岩石岩样的三轴卸围压试验[J].岩石力学与工程学报,1998,17(1):24-29.(YOU Mingqing,HUA Anzeng.Triaxial confining depressure test of rock sample[J].Chinese Journal of Rock Mechanics and Engineering,1998,17(1):24-29.(in Chinese))
[7]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):1 807-1 817.(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):1 807-1 817.(in Chinese))
[8]周科平,胡振襄,李杰林,等.基于核磁共振技术的大理岩卸荷损伤演化规律研究[J].岩石力学与工程学报,2014,33(增2):3 523-3 530.(ZHOU Keping,HU Zhenxiang,LI Jielin,et al.Study of marble damage evolution laws under unloading condition based on nuclear magnetic resonance technique[J].Chinese Journal of Rock Mechanics and Engineering,2014,33(Supp.2):3 523-3 530.(in Chinese))
[9]CAI M,KAISER P K,TASAKA Y,et al.Generalized crack initiation and crack damage stress thresholds of brittle rock masses near underground excavations[J].International Journal of Rock Mechanics and Mining Sciences,2004,41(5):833-847.
[10]张黎明,王在泉,宋全锋,等.粉砂岩卸荷破坏全过程的试验研究[J].岩石力学与工程学报,2005,24(增1):5 043-5 047.(ZHANGLiming,WANG Zaiquan,SONG Quanfeng,et al.Experimental study on the total failure course of silt sand under unloading condition[J].Chinese Journal of Rock Mechanics and Engineering,2005,24(Supp.1):5 043-5 047.(in Chinese))
[11]任建喜,葛修润,蒲毅彬,等.岩石卸荷损伤演化机制CT实时分析初探[J].岩石力学与工程学报,2000,19(6):697-701.(RENJianxi,GE Xiurun,PU Yibin,et al.Primary study of real-time CT testing of unloading damage evolution law of rock[J].Chinese Journal of Rock Mechanics and Engineering,2000,19(6):697-701.(in Chinese))
[12]李天斌,王兰生.卸荷应力状态下玄武岩变形破坏特征的试验研究[J].岩石力学与工程学报,1993,12(4):321-327.(LI Tianbin,WANGLansheng.An experimental study on the deformation and failure features of a basalt under unloading condition[J].Chinese Journal of Rock Mechanics and Engineering,1993,12(4):321-327.(in Chinese))
[13]刘建,李建朋.砂岩高应力峰前卸围压试验研究[J].岩石力学与工程学报,2011,30(3):473-479.(LIU Jian,LI Jianpeng.Experimental research on sandstonepre-peak unloading process under high confining pressure[J].Chinese Journal of Rock Mechanics and Engineering,2011,30(3):473-479.(in Chinese))
[14]尹土兵,李夕兵,王斌,等.高温后砂岩动态压缩条件下力学特性研究[J].岩土工程学报,2011,33(5):777-784.(YIN Tubing,LI Xibing,WANG Bin,et al.Mechanical properties of sandstones after high temperature under dynamic loading[J].Chinese Journal of Geotechnical Engineering,2011,33(5):777-784.(in Chinese))
[15]吴安杰,邓建华,顾乡,等.冻融循环作用下泥质白云岩力学特性及损伤演化规律研究[J].岩土力学,2014,35(11):3 065-3 072.(WU Anjie,DENG Jianhua,GU Xiang,et al.Research on mechanical properties and damage evolution law of argillaceous dolomite under freeze-thaw cycles[J].Rock and Soil Mechnics,2014,35(11):3 065-3 072.(in Chinese))
[16]王伟,龚传根,朱鹏辉,等.大理岩干湿循环力学特性试验研究[J].水利学报,2017,48(10):1 175-1 184.(WANG Wei,GONGChuangen,ZHU Penghui,et al.Experimental study on mechanical properties of marble under hydraulic weathering coupling[J].Journal of Hydraulic Engineering,2017,48(10):1 175-1 184.(in Chinese))
[17]罗丹旎,苏国韶,何保煜.不同饱水度花岗岩的真三轴岩爆试验研究[J].岩土力学,2019,DOI:10.16285/j.rsm.2017.2432.(LUO Danni,SU Guoshao,HE Baoyu.True triaxial test on rockburst of granites with different water saturation[J].Rock and Soil Mechnics,2019,DOI:10.16285/j.rsm.2017.2432.(in Chinese))
[18]李光雷,蔚立元,苏海健,等.化学腐蚀灰岩SHPB冲击动力学性能研究[J].岩石力学与工程学报,2018,37(9):2 075-2 083.(LIGuanglei,YU Liyuan,SU Haijian,et al.Dynamic properties of corroded limestone based on SHPB[J].Chinese Journal of Rock Mechanics and Engineering,2018,37(9):2 075-2 083.(in Chinese))
[19]尤明庆,苏承东,李小双.损伤岩石岩样的力学特性与纵波速度关系研究[J].岩石力学与工程学报,2008,27(3):458-467.(YOUMingqing,SU Chengdong,LI Xiaoshuang.Study on relation between mechanical properties and longitudinal wave velocities for damaged rock samples[J].Chinese Journal of Rock Mechanics and Engineering,2008,27(3):458-467.(in Chinese))
[20]FREW D J,FORRESTAL M J,CHEN W.Pulse shaping techniques for testing brittle materials with a split Hopkinson pressure bar[J].Experimental Mechanics,2002,42(1):93-106.
[21]周子龙,李夕兵,岩小明.岩石SHPB测试中岩样恒应变率变形的加载条件[J].岩石力学与工程学报,2009,28(12):2 445-2 452.(ZHOU Zilong,LI Xibing,YAN Xiaoming.Loading condition for specimen deformation at constant stain rate in SHPB test of rock[J].Chinese Journal of Rock Mechanics and Engineering,2009,28(12):2 445-2 452.(in Chinese))
[22]蔚立元,李光雷,苏海健,等.高温后无烟煤静动态压缩力学特性研究[J].岩石力学与工程学报,2017,36(11):2 712-2 719.(YULiyuan,LI Guanglei,SU Haijian,et al.Experimental study on static and dynamic mechanical properties of anthracite after high temperature heating[J].Chinese Journal of Rock Mechanics and Engineering,201,36(11):2 712-2 719.(in Chinese))
[23]鞠杨,谢和平.基于应变等效性假说的损伤定义的适用条件[J].应用力学学报,1998,15(1):43-49.(JU Yang,XIE Heping.Avariable condition of the damage description based on hypothesis of strain equivalence[J].Chinese Journal of Applied Mechanics,1998,15(1):43-49.(in Chinese))
[24]MENG Q B,ZHANG M W,HAN L J,et al.Acoustic emission characteristics of red sandstone specimens under uniaxial cyclic loading and unloading compression[J].Rock Mechanics and Rock Engineering,2018,51(4):969-988.
[25]王礼立.应力波基础[M].北京:国防工业出版社,2005:52-60.(WANG Lili.Foundation of stress waves[M].Beijing:National Defense Industry Press,2005:52-60.(in Chinese))
[26]宫凤强,王进,李夕兵.岩石压缩特性的率效应与动态增强因子统一模型[J].岩石力学与工程学报,2018,37(7):1 586-1 595.(GONG Fengqiang,WANG Jin,LI Xibing.The rate effect of compression characteristics and a unified model of dynamic increasing factor for rock materials[J].Chinese Journal of Rock Mechanics and Engineering,2018,37(7):1 586-1 595.(in Chinese))
[27]谢和平,鞠杨,黎立云.基于能量耗散与释放原理的岩石强度与整体破坏准则[J].岩石力学与工程学报,2005,24(17):3 003-3 010.(XIE Heping,JU Yang,LI Liyun.Criteria for strength and structural failure of rocks based on energy dissipation and energy release principles[J].Chinese Journal of Rock Mechanics and Engineering,2005,24(17):3 003-3 010.(in Chinese))
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