单轴压类岩石试件应变局部化位置、方向及预警应用研究
|
摘要
应变局部化是岩石破坏的先兆,为揭示单轴压缩条件下控制变形局部化带出现时间、位置和生长方向的主要因素。以白光数字散斑相关方法作为观测手段,获取实验过程中变形局部化的时间演变全过程数据,计算最大主应变场、最小主应变场、位移场,并结合轴力-位移关系曲线对多个试件的局部化演变特征进行了综合对比分析,发现类岩石脆性材料在单轴压受力条件下局部化带的发展沿最大主应变(最大压应变)方向,并随着最大主应变方向的偏转而发生偏转;局部化带的出现位置受最小主应变控制;短时位移场显示脆性类岩石材料局部化带内以张拉破坏为主,并非剪切破坏;局部化带不仅可在接近峰值载荷的高荷载条件下出现,还可能出现在荷载值较低的变形加速拐点处;局部化启动、局部化带两侧观测点水平位移分量反向是较好的构件破坏预警指标。
Strain localization is the warning sign of rock damage. In order to reveal the key mechanical factors that control its occurrence time, position and growth direction, digital image correlation method is used to obtain the whole deformation process of specimens under uniaxial compression tests. The maximum and minimum principal strain field, displacement field are then calculated. Combining with the axial load-displacement curve, the strain localization evolution characteristics of different specimens are compared and analyzed comprehensively. It is found that for brittle rock-like material under uniaxial compression the strain localization belt grows at the direction of maximum principal strain(maximum compressive strain) and deflects with the direction change of maximum principal strain; the position of the strain localization belt is controlled by minimum principal strain; the transient displacement field indicates that damage of brittle rock-like material in the strain localization belt is mainly caused by tensile deformation not shear deformation; strain localization not only occurs at the point close to peak load, but also at the inflection point where deformation accelerates but the load is low; the appearance of localization belt and opposite horizontal displacement vector along the belt are two proper failure prediction indices.
Strain localization is the warning sign of rock damage. In order to reveal the key mechanical factors that control its occurrence time, position and growth direction, digital image correlation method is used to obtain the whole deformation process of specimens under uniaxial compression tests. The maximum and minimum principal strain field, displacement field are then calculated. Combining with the axial load-displacement curve, the strain localization evolution characteristics of different specimens are compared and analyzed comprehensively. It is found that for brittle rock-like material under uniaxial compression the strain localization belt grows at the direction of maximum principal strain(maximum compressive strain) and deflects with the direction change of maximum principal strain; the position of the strain localization belt is controlled by minimum principal strain; the transient displacement field indicates that damage of brittle rock-like material in the strain localization belt is mainly caused by tensile deformation not shear deformation; strain localization not only occurs at the point close to peak load, but also at the inflection point where deformation accelerates but the load is low; the appearance of localization belt and opposite horizontal displacement vector along the belt are two proper failure prediction indices.
引文
[1]潘一山,宋义敏.岩石变形破坏局部化的理论与实验研究[C]//岩石变形破坏局部化的理论与实验研究武汉:中国岩石力学与工程学会,2000.PAN Yi-shan,SONG Yi-min.The study of theory and experiment for deformation-failure localization of rock[C]//The study of theory and experiment for deformation-failure localization of rock.Wuhan:Chinese Society for Rock Mechanics&Engineering,2000.
[2]赵程,田加深,松田浩,等.单轴压缩下基于全局应变场分析的岩石裂纹扩展及其损伤演化特性研究[J].岩石力学与工程学报,2015,34(4):763-769.ZHAO Cheng,TIAN Jia-shen,MATSUDA Hiro-shi,et al.Study on the crack propagation and damage evolution characteristcis of rock based on the global strain field under uniaxial compression[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(4):763-769.
[3]赵程,鲍冲,田加深,等.基于应变局部化的双裂纹岩样贯通模式及强度试验研究[J].岩石力学与工程学报,2015,34(11):2309-2318.ZHAO Cheng,BAO Chong,TIAN Jia-shen,et al.Experimental study of coalescence mode of cracks and strength of rock with double flaws based on strain localization[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(11):2309-2318.
[4]XING H Z,ZHANG Q B,RUAN D,et al,Full-field measurement and fracture characterisations of rocks under dynamic loads using high-speed threedimensional digital image correlation[J].International Journal of Impact Engineering,2018,113:61-72.
[5]宋义敏,马少鹏,杨小彬,等.岩石变形破坏的数字散斑相关方法研究[J].岩石力学与工程学报,2011,30(1):170-175.SONG Yi-min,MA Shao-peng,YANG Xiao-bin,et al.Experimental investigation on failure of rock by digital speckle correlation methods[J].Chinese Journal of Rock Mechanics and Engineering,2011,30(1):170-175.
[6]宋义敏,邢同振,邓琳琳,等.不同加载速率下岩石变形场演化试验研究[J].岩土力学,2017,38(10):2773-2779,2788.SONG Yi-min,XING Tong-zhen,DENG Lin-lin,et al.Experimental study of evolution characteristics of rock deformation field at different loading rates[J].Rock and Soil Mechanics,2017,38(10):2773-2779,2788.
[7]CAO Yan-yan,MA Shao-peng,KANG Yong-jun,et al.The experimental study on fracture process of similar rock material with different ductility[J].Procedia Engineering,2011,26:1798-1802.
[8]潘一山,杨小彬,马少鹏,等.岩土材料变形局部化的实验研究[J].煤炭学报,2002,27(3):281-284.PAN Yi-shan,YANG Xiao-bin,MA Shao-peng,et al.Experimental study on the deformation local ization of rock-soil material[J].Journal of China Coal Society,2002,27(3):281-284.
[9]潘一山,杨小彬.岩石变形破坏局部化的白光数字散斑相关方法研究[J].实验力学,2001,16(2):220-225.PAN Yi-shan,YAN G Xiao-bin.A study on the deformation localization of rocks by white light digital speckle correlation method[J].Journal of Experimental Mechanics,2001,16(2):220-225.
[10]MUNOZ H,TAHERI A.Specimen aspect ratio and progressive field strain development of sandstone under uniaxial compression by three-dimensional digital image correlation[J].Journal of Rock Mechanics and Geotechnical Engineering,2017,9(4):599-610.
[11]SONG H,ZHANG H,FU D,et al.Experimental study on damage evolution of rock under uniform and concentrated loading conditions using digital image correlation[J].Fatigue&Fracture of Engineering Materials&Structures,2013,36(8):760-768.
[12]MUNOZ1 H,TAHERI A,CHANDA E K.Pre-peak and post-peak rock strain characteristics during uniaxial compression by 3D digital image correlation[J].Rock Mechanics and Rock Engineering,2016,49:2541-2554.
[13]CHENG Jian-long,YANG Sheng-qi,CHEN Kui,et al.Uniaxial experimental study of the acoustic emission and deformation behavior of composite rock based on 3D digital image correlation(DIC)[J].Acta Mechanica Sinica,2017,33(6):999-1021.
[14]马少鹏,潘一山,王来贵,等.数字散斑相关方法用于岩石结构破坏过程观测[J].辽宁工程技术大学学报,2005,24(1):51-53.MA Shao-peng,PAN Yi-shan,WANG Lai-gui,et al.Observation of failure procedure of rock structure using digital speckle correlation method[J].Journal of Liaoning Technical University,2005,24(1):51-53.
[15]宋义敏,姜耀东,马少鹏,等.岩石变形破坏全过程的变形场和能量演化研究[J].岩土力学,2012,33(5):1352-1356,1365.SONG Yi-min,JIANG Yao-dong,MA Shao-peng,et al.Evolution of deformation fields and energy in whole process of rock failure[J].Rock and Soil Mechanics,2012,33(5):1352-1356,1365.
[16]宋义敏,邢同振,赵同彬,等.岩石单轴压缩变形场演化的声发射特征研究[J].岩石力学与工程学报,2017,36(3):534-542.SONG Yi-min,XING Tong-zhen,ZHAO Tong-bin,et al.Acoustic emission characteristics of deformation field development of rock under uniaxial loading[J].Chinese Journal of Rock Mechanics and Engineering,2017,36(3):534-542.
[2]赵程,田加深,松田浩,等.单轴压缩下基于全局应变场分析的岩石裂纹扩展及其损伤演化特性研究[J].岩石力学与工程学报,2015,34(4):763-769.ZHAO Cheng,TIAN Jia-shen,MATSUDA Hiro-shi,et al.Study on the crack propagation and damage evolution characteristcis of rock based on the global strain field under uniaxial compression[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(4):763-769.
[3]赵程,鲍冲,田加深,等.基于应变局部化的双裂纹岩样贯通模式及强度试验研究[J].岩石力学与工程学报,2015,34(11):2309-2318.ZHAO Cheng,BAO Chong,TIAN Jia-shen,et al.Experimental study of coalescence mode of cracks and strength of rock with double flaws based on strain localization[J].Chinese Journal of Rock Mechanics and Engineering,2015,34(11):2309-2318.
[4]XING H Z,ZHANG Q B,RUAN D,et al,Full-field measurement and fracture characterisations of rocks under dynamic loads using high-speed threedimensional digital image correlation[J].International Journal of Impact Engineering,2018,113:61-72.
[5]宋义敏,马少鹏,杨小彬,等.岩石变形破坏的数字散斑相关方法研究[J].岩石力学与工程学报,2011,30(1):170-175.SONG Yi-min,MA Shao-peng,YANG Xiao-bin,et al.Experimental investigation on failure of rock by digital speckle correlation methods[J].Chinese Journal of Rock Mechanics and Engineering,2011,30(1):170-175.
[6]宋义敏,邢同振,邓琳琳,等.不同加载速率下岩石变形场演化试验研究[J].岩土力学,2017,38(10):2773-2779,2788.SONG Yi-min,XING Tong-zhen,DENG Lin-lin,et al.Experimental study of evolution characteristics of rock deformation field at different loading rates[J].Rock and Soil Mechanics,2017,38(10):2773-2779,2788.
[7]CAO Yan-yan,MA Shao-peng,KANG Yong-jun,et al.The experimental study on fracture process of similar rock material with different ductility[J].Procedia Engineering,2011,26:1798-1802.
[8]潘一山,杨小彬,马少鹏,等.岩土材料变形局部化的实验研究[J].煤炭学报,2002,27(3):281-284.PAN Yi-shan,YANG Xiao-bin,MA Shao-peng,et al.Experimental study on the deformation local ization of rock-soil material[J].Journal of China Coal Society,2002,27(3):281-284.
[9]潘一山,杨小彬.岩石变形破坏局部化的白光数字散斑相关方法研究[J].实验力学,2001,16(2):220-225.PAN Yi-shan,YAN G Xiao-bin.A study on the deformation localization of rocks by white light digital speckle correlation method[J].Journal of Experimental Mechanics,2001,16(2):220-225.
[10]MUNOZ H,TAHERI A.Specimen aspect ratio and progressive field strain development of sandstone under uniaxial compression by three-dimensional digital image correlation[J].Journal of Rock Mechanics and Geotechnical Engineering,2017,9(4):599-610.
[11]SONG H,ZHANG H,FU D,et al.Experimental study on damage evolution of rock under uniform and concentrated loading conditions using digital image correlation[J].Fatigue&Fracture of Engineering Materials&Structures,2013,36(8):760-768.
[12]MUNOZ1 H,TAHERI A,CHANDA E K.Pre-peak and post-peak rock strain characteristics during uniaxial compression by 3D digital image correlation[J].Rock Mechanics and Rock Engineering,2016,49:2541-2554.
[13]CHENG Jian-long,YANG Sheng-qi,CHEN Kui,et al.Uniaxial experimental study of the acoustic emission and deformation behavior of composite rock based on 3D digital image correlation(DIC)[J].Acta Mechanica Sinica,2017,33(6):999-1021.
[14]马少鹏,潘一山,王来贵,等.数字散斑相关方法用于岩石结构破坏过程观测[J].辽宁工程技术大学学报,2005,24(1):51-53.MA Shao-peng,PAN Yi-shan,WANG Lai-gui,et al.Observation of failure procedure of rock structure using digital speckle correlation method[J].Journal of Liaoning Technical University,2005,24(1):51-53.
[15]宋义敏,姜耀东,马少鹏,等.岩石变形破坏全过程的变形场和能量演化研究[J].岩土力学,2012,33(5):1352-1356,1365.SONG Yi-min,JIANG Yao-dong,MA Shao-peng,et al.Evolution of deformation fields and energy in whole process of rock failure[J].Rock and Soil Mechanics,2012,33(5):1352-1356,1365.
[16]宋义敏,邢同振,赵同彬,等.岩石单轴压缩变形场演化的声发射特征研究[J].岩石力学与工程学报,2017,36(3):534-542.SONG Yi-min,XING Tong-zhen,ZHAO Tong-bin,et al.Acoustic emission characteristics of deformation field development of rock under uniaxial loading[J].Chinese Journal of Rock Mechanics and Engineering,2017,36(3):534-542.