基于数字图像相关技术的土体干缩开裂过程研究
|
摘要
在干燥条件下,土体极易蒸发失水收缩产生开裂,深入研究土体干缩开裂过程对准确掌握干旱气候环境中的土体工程性质响应特性具有重要意义。通过对黏性土开展室内干燥试验,采用数码相机实时记录土体表面裂隙的动态发育过程,结合数字图像相关技术,获取土体收缩开裂全过程。结果表明:①裂隙通常在土体表面张拉应力集中处产生,裂隙产生后周围应力场得到迅速释放并发生重排,且裂隙间倾向于成直角相交;②土体表面的位移场和应变场可以有效反映土体收缩开裂过程中的动态特征,能为分析和预测裂隙的演化过程提供重要参考信息;③土体被裂隙分割成不同的块区,每个块区在收缩过程中都存在收缩中心现象,且各块区的收缩中心位置会随时间而变化;④数字图像相关技术能有效识别不同图像之间的灰度特征值,能在完全不扰动土样的条件下准确获取土体表面干缩变形信息的时空演化特征,为研究土体干缩开裂动态过程及机理提供了优越的技术手段,具有较好的推广价值。
Under dry condition, the soil is prone to evaporation, leading to desiccation cracking. It is of great significance to deeply study the desiccation cracking process of soils to accurately grasp the engineering response characteristics of soils in arid climate environment. In conducting laboratory drying tests on cohesive soils, digital cameras are used to record the dynamic development of surface cracks in real time. By using the digital image correlation techniques, the plane strain field and displacement field of the whole process of desiccation cracking of soils are obtained. The experimental results show that:(1)The cracks are usually generated at the position where the tensile stress is concentrated, and the stress is then rearranged when the surrounding stress is rapidly released, and the cracks tend to intersect with other cracks at right angles.(2) The displacement field and strain field can effectively confirm some movement characteristics of the soils during the desiccation cracking process,thus providing assistance for analyzing the dynamic evolution process of cracks.(3) The soils are divided into different blocks by cracks, each block has its shrinkage center, and the shrinkage center will change with time.(4) The digital image correlation technique can effectively identify the gray scale feature values between different images, obtain the surface deformation information, and provide valid technical means for the study on desiccation cracking characteristics of soils.
Under dry condition, the soil is prone to evaporation, leading to desiccation cracking. It is of great significance to deeply study the desiccation cracking process of soils to accurately grasp the engineering response characteristics of soils in arid climate environment. In conducting laboratory drying tests on cohesive soils, digital cameras are used to record the dynamic development of surface cracks in real time. By using the digital image correlation techniques, the plane strain field and displacement field of the whole process of desiccation cracking of soils are obtained. The experimental results show that:(1)The cracks are usually generated at the position where the tensile stress is concentrated, and the stress is then rearranged when the surrounding stress is rapidly released, and the cracks tend to intersect with other cracks at right angles.(2) The displacement field and strain field can effectively confirm some movement characteristics of the soils during the desiccation cracking process,thus providing assistance for analyzing the dynamic evolution process of cracks.(3) The soils are divided into different blocks by cracks, each block has its shrinkage center, and the shrinkage center will change with time.(4) The digital image correlation technique can effectively identify the gray scale feature values between different images, obtain the surface deformation information, and provide valid technical means for the study on desiccation cracking characteristics of soils.
引文
[1]TOWNER G D.The influence of sand‐and silt‐size particles on the cracking during drying of small clay‐dominated aggregates[J].European Journal of Soil Science,1988,39(3):347-356.
[2]MORRIS P H,GRAHAM J,WILLIAMS D J.Cracking in drying soils[J].Canadian Geotechnical Journal,1992,29(2):263-277.
[3]WEINBERGER R.Initiation and growth of cracks during desiccation of stratified muddy sediments[J].Journal of Structural Geology,1999,21(4):379-386.
[4]KODIKARA J,COSTA S.Desiccation cracking in clayey soils:mechanisms and modelling[M].Heidelberg:Springer,2013:21-32.
[5]TANG C,SHI B,LIU C,et al.Influencing factors of geometrical structure of surface shrinkage cracks in clayey soils[J].Engineering Geology,2008,101(3):204-217.
[6]TANG C S,CUI Y J,TANG A M,et al.Experiment evidence on the temperature dependence of desiccation cracking behavior of clayey soils.Eng.Geol,2010,114(3/4):261-266.
[7]BAKER R.Tensile strength,tension cracks,and stability of slopes[J].Soils&Foundations,1981,21(2):1-19.
[8]袁俊平.非饱和膨胀土裂隙的量化模型与边坡稳定性研究[J].南京:河海大学,2003.(YUAN Jun-ping.Quantification model and slope stability of unsaturated expansive soil crack[J].Nanjing:Hohai University,2003.(in Chinese))
[9]殷宗泽,袁俊平,韦杰,等.论裂隙对膨胀土边坡稳定的影响[J].岩土工程学报,2012,34(12):2155-2161.(YINZong-ze,YUAN Jun-ping,WEI Jie,et al.Influences of fissures on slope stability of expansive soil[J].Chinese Journal of Geotechnical Engineering,2012,34(12):2155-2161.(in Chinese))
[10]KRISNANTO S,RAHARDJO H,FREDLUND D G,et al.Mapping of cracked soils and lateral water flow characteristics through a network of cracks[J].Engineering Geology,2014,172(5):12-25.
[11]KLEPPE J H,OLSON R E.Desiccation cracking of soil barriers[M].JOHNSON A J,FROBEL R K,CAVALLIS N J,et al,eds.Hydraulic Barriers in Soil&Rock.Philadephia:ASTM,1985,874:13.
[12]MILLER C J,MI H,YESILLER N.Experimental analysis of desiccation crack propagation in clay liners[J].Journal of the American Water Resources Association,1998,34(3):677-686.
[13]ALBRECHT B A,BENSON C H.Effect of desiccation on compacted natural clays[J].Journal of Geotechnical&Geoenvironmental Engineering,2001,127(1):67-75.
[14]FOSTER M,FELL R,SPANNAGLE M.The statistics of embankment dam failures and accidents[J].Canadian Geotechnical Journal,2011,37(5):1000-1024.
[15]YESILLER N,MILLER C J,INCI G,et al.Desiccation and cracking behavior of three compacted landfill liner soils[J].Engineering Geology,2000,57(1):105-121.
[16]GUIDI G,PAGLIAI M,PETRUZZELLI G.Quantitative size evaluation of cracks and clods in artificially dried soil samples[J].Geoderma,1978,20(2):105-113.
[17]DE-LIMA O A L,SHARMA M M.A generalized Maxwell-Wagner theory for membrane polarization in shalysands[J].Geophysics,1992,57(3):431-440.
[18]GILL D R,LEHANE B M.An optical technique for investigating soil displacement patterns[J].Geotechnical Testing Journal,2001,24(3):324-329.
[19]KAHN-JETTER Z L,CHU T C.Three-dimensional displacement measurement using digital image correlation and photogrammic analysis[J].Experimental Mechanics,1990,30:10-16.
[20]李元海,靖洪文,朱合华,等.数字照相量测在砂土地基离心试验中的应用[J].岩土工程学报,2006,28(3):306-311.(LI Yuan-hai,JING Hong-wen,ZHU He-hua,et al.Experimental investigation on progressive deformation patterns of sand foundation in centrifuge test using digital photogrammetry[J].Chinese Journal of Geotechnical Engineering,2006,28(3):306-311.(in Chinese))
[21]LEE D,TIPPUR H,KIRUGULIGE M.Experimental study of dynamic crack growth in unidirectional graphite/epoxy using digital image correlation method and high-speed photography[J].Journal of Composite Materials,2009,43(19):2081-2108.
[22]赵程,鲍冲,松田浩,等.数字图像技术在节理岩体裂纹扩展试验中的应用研究[J].岩土工程学报,2015,37(5):944-951.(ZHAO Cheng,BAO Chong,SONGTian-hao,et al.Application of digital image correlation method in experimental research on crack propagation of brittle rock[J].Chinese Journal of Geotechnical Engineering,2015,37(5):944-951.(in Chinese))
[23]张昕,乐金朝,刘汉东.砂土中群锚锚周土体变形特性模型试验研究[J].岩土力学,2016,37(增刊1):240-248.(ZHANG Xin,YUE Jin-chao,LIU Han-dong.Experimental study of soil deformation around group anchors in sand[J].Rock and Soil Mechanics,2016,37(S1):240-248.(in Chinese))
[24]TENG Y,STANIER S,GOURVENEC S M.Synchronised multi-scale image analysis of soil deformations[J].International Journal of Physical Modelling in Geotechnics,2017,17(1).
[25]YAMAGUCHI I.A laser-speckle strain gauge[J].Journal of Physics E:Scientific Instruments,1981,14(14):1270-1273.
[26]RANSON W F,PETERS W H.Digital image techniques in experimental stress analysis[J].Optical Engineering,1982,21(3):427-431.
[27]NAHLAWI H,KODIKARA J K.Laboratory experiments on desiccation cracking of thin soil layers[J].Geotechnical and Geological Engineering,2006,24:1641-1664.
[28]CORTE A,HIGASHI A.Experimental research on desiccation cracks in soil[R].Illinois:Army Snow Ice and Permafrost Research Establishment,1960.
[29]TANG C S,SHI B,LIU C,et al.Experimental characterization of shrinkage and desiccation cracking in thin clay layer[J].Applied Clay Science,2011,52(1):69-77.
[2]MORRIS P H,GRAHAM J,WILLIAMS D J.Cracking in drying soils[J].Canadian Geotechnical Journal,1992,29(2):263-277.
[3]WEINBERGER R.Initiation and growth of cracks during desiccation of stratified muddy sediments[J].Journal of Structural Geology,1999,21(4):379-386.
[4]KODIKARA J,COSTA S.Desiccation cracking in clayey soils:mechanisms and modelling[M].Heidelberg:Springer,2013:21-32.
[5]TANG C,SHI B,LIU C,et al.Influencing factors of geometrical structure of surface shrinkage cracks in clayey soils[J].Engineering Geology,2008,101(3):204-217.
[6]TANG C S,CUI Y J,TANG A M,et al.Experiment evidence on the temperature dependence of desiccation cracking behavior of clayey soils.Eng.Geol,2010,114(3/4):261-266.
[7]BAKER R.Tensile strength,tension cracks,and stability of slopes[J].Soils&Foundations,1981,21(2):1-19.
[8]袁俊平.非饱和膨胀土裂隙的量化模型与边坡稳定性研究[J].南京:河海大学,2003.(YUAN Jun-ping.Quantification model and slope stability of unsaturated expansive soil crack[J].Nanjing:Hohai University,2003.(in Chinese))
[9]殷宗泽,袁俊平,韦杰,等.论裂隙对膨胀土边坡稳定的影响[J].岩土工程学报,2012,34(12):2155-2161.(YINZong-ze,YUAN Jun-ping,WEI Jie,et al.Influences of fissures on slope stability of expansive soil[J].Chinese Journal of Geotechnical Engineering,2012,34(12):2155-2161.(in Chinese))
[10]KRISNANTO S,RAHARDJO H,FREDLUND D G,et al.Mapping of cracked soils and lateral water flow characteristics through a network of cracks[J].Engineering Geology,2014,172(5):12-25.
[11]KLEPPE J H,OLSON R E.Desiccation cracking of soil barriers[M].JOHNSON A J,FROBEL R K,CAVALLIS N J,et al,eds.Hydraulic Barriers in Soil&Rock.Philadephia:ASTM,1985,874:13.
[12]MILLER C J,MI H,YESILLER N.Experimental analysis of desiccation crack propagation in clay liners[J].Journal of the American Water Resources Association,1998,34(3):677-686.
[13]ALBRECHT B A,BENSON C H.Effect of desiccation on compacted natural clays[J].Journal of Geotechnical&Geoenvironmental Engineering,2001,127(1):67-75.
[14]FOSTER M,FELL R,SPANNAGLE M.The statistics of embankment dam failures and accidents[J].Canadian Geotechnical Journal,2011,37(5):1000-1024.
[15]YESILLER N,MILLER C J,INCI G,et al.Desiccation and cracking behavior of three compacted landfill liner soils[J].Engineering Geology,2000,57(1):105-121.
[16]GUIDI G,PAGLIAI M,PETRUZZELLI G.Quantitative size evaluation of cracks and clods in artificially dried soil samples[J].Geoderma,1978,20(2):105-113.
[17]DE-LIMA O A L,SHARMA M M.A generalized Maxwell-Wagner theory for membrane polarization in shalysands[J].Geophysics,1992,57(3):431-440.
[18]GILL D R,LEHANE B M.An optical technique for investigating soil displacement patterns[J].Geotechnical Testing Journal,2001,24(3):324-329.
[19]KAHN-JETTER Z L,CHU T C.Three-dimensional displacement measurement using digital image correlation and photogrammic analysis[J].Experimental Mechanics,1990,30:10-16.
[20]李元海,靖洪文,朱合华,等.数字照相量测在砂土地基离心试验中的应用[J].岩土工程学报,2006,28(3):306-311.(LI Yuan-hai,JING Hong-wen,ZHU He-hua,et al.Experimental investigation on progressive deformation patterns of sand foundation in centrifuge test using digital photogrammetry[J].Chinese Journal of Geotechnical Engineering,2006,28(3):306-311.(in Chinese))
[21]LEE D,TIPPUR H,KIRUGULIGE M.Experimental study of dynamic crack growth in unidirectional graphite/epoxy using digital image correlation method and high-speed photography[J].Journal of Composite Materials,2009,43(19):2081-2108.
[22]赵程,鲍冲,松田浩,等.数字图像技术在节理岩体裂纹扩展试验中的应用研究[J].岩土工程学报,2015,37(5):944-951.(ZHAO Cheng,BAO Chong,SONGTian-hao,et al.Application of digital image correlation method in experimental research on crack propagation of brittle rock[J].Chinese Journal of Geotechnical Engineering,2015,37(5):944-951.(in Chinese))
[23]张昕,乐金朝,刘汉东.砂土中群锚锚周土体变形特性模型试验研究[J].岩土力学,2016,37(增刊1):240-248.(ZHANG Xin,YUE Jin-chao,LIU Han-dong.Experimental study of soil deformation around group anchors in sand[J].Rock and Soil Mechanics,2016,37(S1):240-248.(in Chinese))
[24]TENG Y,STANIER S,GOURVENEC S M.Synchronised multi-scale image analysis of soil deformations[J].International Journal of Physical Modelling in Geotechnics,2017,17(1).
[25]YAMAGUCHI I.A laser-speckle strain gauge[J].Journal of Physics E:Scientific Instruments,1981,14(14):1270-1273.
[26]RANSON W F,PETERS W H.Digital image techniques in experimental stress analysis[J].Optical Engineering,1982,21(3):427-431.
[27]NAHLAWI H,KODIKARA J K.Laboratory experiments on desiccation cracking of thin soil layers[J].Geotechnical and Geological Engineering,2006,24:1641-1664.
[28]CORTE A,HIGASHI A.Experimental research on desiccation cracks in soil[R].Illinois:Army Snow Ice and Permafrost Research Establishment,1960.
[29]TANG C S,SHI B,LIU C,et al.Experimental characterization of shrinkage and desiccation cracking in thin clay layer[J].Applied Clay Science,2011,52(1):69-77.
© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号 地址：北京市海淀区学院路29号 邮编：100083 电话：办公室：(+86 10)66554848；文献借阅、咨询服务、科技查新：66554700 |