化学腐蚀作用下黑云片岩峰后应变软化特性研究
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摘要
为探索地下水腐蚀作用下黑云片岩的峰后应变软化特性,采用人工配置的酸性溶液对黑云片岩开展化学腐蚀,并对腐蚀后的岩石进行三轴压缩试验,得到不同腐蚀时间黑云片岩的全应力-应变曲线。在试验基础上分析腐蚀作用下岩石的峰后应变软化规律,获得了化学腐蚀作用下黑云片岩的黏聚力和内摩擦角变化规律;将峰值应力与残余应力的算数平均数定义为软化应力,拟合了峰后软化应力、软化模量与腐蚀时间的函数关系,基于Mohr-Coulomb屈服准则,构建考虑腐蚀时间的黑云片岩峰后应变软化模型并基于FLAC3D平台进行了二次开发,利用开发后的应变软化模型进行三轴压缩试验的数值模拟。研究结果表明:随着腐蚀时间的增加,黑云片岩的峰后黏聚力与内摩擦角均呈减小的趋势,应变软化速率增加,软化程度提高,岩石从脆性转为延性,峰值强度与残余强度之间的间距逐渐减小;数值模拟的结果与试验数据吻合较好,说明论文构建的应变软化模型具有较好的可靠性。
In order to explore the post-peak strain softening characteristics of biotite schist under the influence of corrosive effect of groundwater, manmade acidic solutions were used to conduct chemical corrosion on biotite schist, and then the triaxial compression tests of the eroded rocks were carried out, thus obtaining the whole stress-strain curve of biotite schist during different corrosion time. On the basis of experiments, the post-peak strain-softening laws of eroded rocks were analyzed, and the variation of cohesion and internal friction angle of biotite schist under the influence of corrosive effect was learned. The arithmetic mean of peak stress and residual stress was defined as softening stress, combined with the functional ration of post-peak softening stress, softening modulus and corrosion time, and the post-peak strain softening model of biotite schist based on Mohr-Coulomb yield criteria was constructed, with corrosion time taken into consideration. The secondary development based on FLAC3D platform, and the strain softening model was used for numerical simulation of triaxial compression tests. Research shows that as corrosion time increases, post-peak cohesion and internal friction angle of biotite schist both drop, with strain-softening rate and softening level up; rocks turn ductile from being brittle, and the spacing between peak strength and residual shear strength decreases; the results of numerical simulation coincide well with the experimental data, which demonstrates the strain-softening model constructed in the paper is quite reliable.
In order to explore the post-peak strain softening characteristics of biotite schist under the influence of corrosive effect of groundwater, manmade acidic solutions were used to conduct chemical corrosion on biotite schist, and then the triaxial compression tests of the eroded rocks were carried out, thus obtaining the whole stress-strain curve of biotite schist during different corrosion time. On the basis of experiments, the post-peak strain-softening laws of eroded rocks were analyzed, and the variation of cohesion and internal friction angle of biotite schist under the influence of corrosive effect was learned. The arithmetic mean of peak stress and residual stress was defined as softening stress, combined with the functional ration of post-peak softening stress, softening modulus and corrosion time, and the post-peak strain softening model of biotite schist based on Mohr-Coulomb yield criteria was constructed, with corrosion time taken into consideration. The secondary development based on FLAC3D platform, and the strain softening model was used for numerical simulation of triaxial compression tests. Research shows that as corrosion time increases, post-peak cohesion and internal friction angle of biotite schist both drop, with strain-softening rate and softening level up; rocks turn ductile from being brittle, and the spacing between peak strength and residual shear strength decreases; the results of numerical simulation coincide well with the experimental data, which demonstrates the strain-softening model constructed in the paper is quite reliable.
引文
[1]王军祥,姜谙男.岩石应变软化本构模型建立及NR-AL法求解研究[J].岩土力学,2015,36(2):393-402.WANG Junxiang,JIANG Annan.Establishing strain softening constitutive model of rock and solution of NR-AL method[J].Rock and Soil Mechanics,2015,36(2):393-402.
[2]王水林,郑宏,刘泉声,等.应变软化岩体分析原理及其应用[J].岩土力学,2014,35(3):609-622.WANG Shuilin,ZHENG Hong,LIU Quansheng,et al.Principle of analysis of strain-softening rock mass and its application[J].Rock and Soil Mechanics,2014,35(3):609-622.
[3]平洋,李树忱,汪雷.贯通节理砂岩峰后变形试验研究及其在隧道支护中的应用[J].煤炭学报,2014,39(4):644-650.PING Yang,LI Shuchen,WANG Lei.Experimental study of post-peak deformation of sandstone with pre-existing transfixion joint and its application in tunnel support[J].Journal of China Coal Society,2014,39(4):644-650.
[4]WANG Shuilin,YIN Shunde.A closed-form solution for a spherical cavity in the elastic-brittle-plastic medium[J].Tunnelling and Underground Space Technology,2011,26(1):236-241
[5]Alejano L R,Alonso E,Rodriguez-dono A,et al.Application of the convergence-confinement method to tunnels in rock masses exhibiting Hoke-Brown strain-softening behavior[J].International Journal of Rock Mechanics and Mining Sciences,2010,47:150-160.
[6]王少辉,邹金锋.基于无量纲法的应变软化围岩的逐步位移法解析[J].铁道科学与工程学报,2017,14(3):507-513.WANG Shaohui,ZOU Jinfeng.Dimensionless analysis of numerical stepwise procedure in strain-softening rock mass[J].Journal of Railway Science and Engineering,2017,14(3):507-513.
[7]WANG Shuilin,YIN Xiaotao,TANG Hua,et al.A new approach for analyzing circular tunnel in strain-softening rock masses[J].International Journal of Rock Mechanics and Mining Sciences,2010,47(1):170-178.
[8]李晓宁,巫锡勇,高姝妹,等.化学腐蚀下红层软岩单轴压缩及声发射特征试验研究[J].铁道科学与工程学报,2015,12(6):1336-1340.LI Xiaoning,WU Xiyong,GAO Shumei,et al.Experiment study on uniaxial compression acoustic emission characteristics of red-bed soft rock in chemical environment[J].Journal of Railway Science and Engineering,2015,12(6):1336-1340.
[9]韩铁林,师俊平,陈蕴生.砂岩在化学腐蚀和冻融循环共同作用下力学特征劣化的试验研究[J].水利学报,2016,47(5):644-655.HAN Tielin,SHI Junping,CHEN Yunsheng.Laboratory investigations on the mechanical properties degradation of sandstone under the combined action between water chemical corrosion and freezing and thawing cycles[J].Journal of Hydraulic Engineering,2016,47(5):644-655.
[10]QIAO Liping,WANG Zhechao,HUANG Anda.Alteration of mesoscopic properties and mechanical behavior of sandstone due to hydro-physical and hydrochemical effects[J].Rock Mechanics and Rock Engineering,2017,50(2):255-267.
[11]Joseph T G.Estimation of the post-failure stiffness of rock[D].Alberta,Canada:University of Alberta,2000.
[12]孙闯,张树光,贾宝新,等.花岗岩峰后力学特性试验与模型研究[J].岩土工程学报,2015,37(5):847-852.SUN Chuang,ZHANG Shuguang,JIA Baoxin,et al.Physical and numerical model tests on post-peak mechanical properties of granite[J].Chinese Journal of Geotechnical Engineering,2015,37(5):847-852.
[13]沈华章,王水林,刘泉声.模拟应变软化岩石三轴试验过程曲线[J].岩土力学,2014,35(6):1647-1654.SHEN Huazhang,WANG Shuilin,LIU Quansheng.Simulation of constitutive curves for strain-softening rock in triaxial compression[J].Rock and Soil Mechanics,2014,35(6):1647-1654.
[14]陈育民,徐鼎平.FLAC\FLAC3D基础与工程实例[M].北京:中国水利水电出版社,2013.CHEN Yumin,XU Dingping.FLAC\FLAC3D foundation and engineering examples[M].Beijing:China Water&Power Press,2013.
[2]王水林,郑宏,刘泉声,等.应变软化岩体分析原理及其应用[J].岩土力学,2014,35(3):609-622.WANG Shuilin,ZHENG Hong,LIU Quansheng,et al.Principle of analysis of strain-softening rock mass and its application[J].Rock and Soil Mechanics,2014,35(3):609-622.
[3]平洋,李树忱,汪雷.贯通节理砂岩峰后变形试验研究及其在隧道支护中的应用[J].煤炭学报,2014,39(4):644-650.PING Yang,LI Shuchen,WANG Lei.Experimental study of post-peak deformation of sandstone with pre-existing transfixion joint and its application in tunnel support[J].Journal of China Coal Society,2014,39(4):644-650.
[4]WANG Shuilin,YIN Shunde.A closed-form solution for a spherical cavity in the elastic-brittle-plastic medium[J].Tunnelling and Underground Space Technology,2011,26(1):236-241
[5]Alejano L R,Alonso E,Rodriguez-dono A,et al.Application of the convergence-confinement method to tunnels in rock masses exhibiting Hoke-Brown strain-softening behavior[J].International Journal of Rock Mechanics and Mining Sciences,2010,47:150-160.
[6]王少辉,邹金锋.基于无量纲法的应变软化围岩的逐步位移法解析[J].铁道科学与工程学报,2017,14(3):507-513.WANG Shaohui,ZOU Jinfeng.Dimensionless analysis of numerical stepwise procedure in strain-softening rock mass[J].Journal of Railway Science and Engineering,2017,14(3):507-513.
[7]WANG Shuilin,YIN Xiaotao,TANG Hua,et al.A new approach for analyzing circular tunnel in strain-softening rock masses[J].International Journal of Rock Mechanics and Mining Sciences,2010,47(1):170-178.
[8]李晓宁,巫锡勇,高姝妹,等.化学腐蚀下红层软岩单轴压缩及声发射特征试验研究[J].铁道科学与工程学报,2015,12(6):1336-1340.LI Xiaoning,WU Xiyong,GAO Shumei,et al.Experiment study on uniaxial compression acoustic emission characteristics of red-bed soft rock in chemical environment[J].Journal of Railway Science and Engineering,2015,12(6):1336-1340.
[9]韩铁林,师俊平,陈蕴生.砂岩在化学腐蚀和冻融循环共同作用下力学特征劣化的试验研究[J].水利学报,2016,47(5):644-655.HAN Tielin,SHI Junping,CHEN Yunsheng.Laboratory investigations on the mechanical properties degradation of sandstone under the combined action between water chemical corrosion and freezing and thawing cycles[J].Journal of Hydraulic Engineering,2016,47(5):644-655.
[10]QIAO Liping,WANG Zhechao,HUANG Anda.Alteration of mesoscopic properties and mechanical behavior of sandstone due to hydro-physical and hydrochemical effects[J].Rock Mechanics and Rock Engineering,2017,50(2):255-267.
[11]Joseph T G.Estimation of the post-failure stiffness of rock[D].Alberta,Canada:University of Alberta,2000.
[12]孙闯,张树光,贾宝新,等.花岗岩峰后力学特性试验与模型研究[J].岩土工程学报,2015,37(5):847-852.SUN Chuang,ZHANG Shuguang,JIA Baoxin,et al.Physical and numerical model tests on post-peak mechanical properties of granite[J].Chinese Journal of Geotechnical Engineering,2015,37(5):847-852.
[13]沈华章,王水林,刘泉声.模拟应变软化岩石三轴试验过程曲线[J].岩土力学,2014,35(6):1647-1654.SHEN Huazhang,WANG Shuilin,LIU Quansheng.Simulation of constitutive curves for strain-softening rock in triaxial compression[J].Rock and Soil Mechanics,2014,35(6):1647-1654.
[14]陈育民,徐鼎平.FLAC\FLAC3D基础与工程实例[M].北京:中国水利水电出版社,2013.CHEN Yumin,XU Dingping.FLAC\FLAC3D foundation and engineering examples[M].Beijing:China Water&Power Press,2013.