单轴压缩湿土样最大剪切应变场数字图像相关方法结果的统计分析

王学滨; 张楠; 潘一山; 杜亚志

doi:10.11779/CJGE201606004

单轴压缩湿土样最大剪切应变场数字图像相关方法结果的统计分析 English Version

王学滨^{1, 2, 3},
张楠²,
潘一山²,
杜亚志²

1. 中国矿业大学(北京)力学与建筑工程学院,北京 100083；
2. 辽宁工程技术大学力学与工程学院,辽宁阜新 123000；
3. 辽宁工程技术大学计算力学研究所,辽宁阜新 123000

基金项目: 国家自然科学基金项目（51374122）; 高等学校博士点专项科研基金项目（20132121110006）; 辽宁省科学事业公益研究基金项目（GY2014-C-008）

详细信息

作者简介:
王学滨（1975- ）,男,黑龙江双鸭山人,博士,教授,博士生导师,主要从事岩土材料的变形、破坏及稳定性研究。E-mail: wxbbb@263.net。

计量
- 文章访问数: 503
- HTML全文浏览量: 1
- PDF下载量: 450
出版历程
- 收稿日期: 2015-05-24
- 发布日期: 2016-06-24

Statistial analyses of maximum shear strain fields for wet soil specimens in uniaxial compression using digital image correlation

1. School of Mechanics and Architecture Engineering, China University of Mining and Technology, Beijing 100083, China;
2. College of Mechanics and Engineering, Liaoning Technical University, Fuxin 123000, China;
3. Institute of Computational Mechanics, Liaoning Technical University, Fuxin 123000, China

摘要

摘要: 研究了单轴压缩湿土样沿剪切带方向的最大剪切应变的均值和标准差以及剪切局部化区域尺寸的演变规律。为了深入揭示土样剪切带萌生的过程,根据纵向应变较高时清晰剪切带所处位置在土样上布置测线,对由数字图像相关方法获得的结果进行双三次样条插值,从而获得测线上光滑性较好的最大剪切应变分布。研究发现,随着纵向应变的增加,沿剪切带方向的最大剪切应变由低值多峰向高值少峰转变。测线上最大剪切应变发生突增的点、局部高值点及低值点均有可能发展成为主峰。测线上最大剪切应变的均值和标准差随纵向应变的演变规律在总体上均呈上凹形,但当纵向应变较低时,二者均呈线性。以上述两种统计量线性规律丧失所对应的平均最大剪切应变作为剪切带萌生的条件。随着纵向应变的增加,土样中发生剪切局部化的区域越来越大。欲达到相同的剪切局部化区域尺寸,含水率高的土样所要求的纵向应变较高。当纵向应变较高时,含水率高的土样的剪切局部化区域尺寸比含水率低的土样要大,这与其塑性变形阶段较长有关。
- 湿土样 /
- 剪切带 /
- 最大剪切应变 /
- 统计 /
- 剪切局部化
Abstract: The evolution of the mean and standard deviations of the maximum shear strains for wet soil specimens in uniaxial compression and the size of the shear localization region are studied. To explore the occurrence and development of shear bands, some monitored lines are arranged in the specimens according to the positions of apparent shear bands at higher longitudinal strains. The maximum shear strains at these lines are obtained using a bicubic spline interpolation function with good smoothness from the results based on the digital image correlation method. It is found that the distribution of the maximum shear strains along shear bands transits from several peaks with lower values to a few main peaks with higher values with the increase of the longitudinal strain. These main peaks originate from the positions where the maximum shear strains increase rapidly and from those with local higher or lower values. Generally, the mean and standard deviations of the maximum shear strains at monitored lines are convex upwards with the increase of the longitudinal strain. However, at lower longitudinal strains, the two statistical quantities are linear. The mean of the maximum shear strain corresponding to the end of the linear stage of statistical quantities is regarded as the occurrence of shear bands. The size of the shear localization region increases with the increase of the longitudinal strain. For the same size of the shear localization region, the specimens with higher water contents require higher longitudinal strains. At higher longitudinal strains, the size of the shear localization region for the specimens with higher water contents is larger than that with lower water contents, which is related to its longer stage of plastic deformation.
- wet soil specimen /
- shear band /
- maximum shear strain /
- statistics /
- shear localization

HTML全文

参考文献(13)

[1]	HALL S A, BORNERT M, DESRUES J, et al. Discrete and continuum analysis of localised deformation in sand using X-ray μCT and volumetric digital image correlation[J]. Géotechnique, 2010, 60(5): 315-322.
[2]	MICHALOWSKI R L, SHI L. Deformation patterns of reinforced foundation sand at failure[J]. Journal of Geotechnical and Geoenvironmental Engineering, ASCE, 2003, 129(6): 439-449.
[3]	黄茂松, 李学丰, 钱建固. 各向异性砂土的应变局部化分析[J]. 岩土工程学报, 2012, 34(10): 1772-1780. (HUANG Mao-song, LI Xue-feng, QIAN Jian-gu. Strain localization of anisotropic sand[J]. Chinese Journal of Geotechnical Engineering, 2012, 34(10): 1772-1780. (in Chinese))
[4]	蒋明镜, 彭镝, 申志福, 等. 深海能源土剪切带形成机理离散元分析[J]. 岩土工程学报, 2014, 36(9): 1624-1630. (JIANG Ming-jing, PENG Di, SHEN Zhi-fu, et al. DEM analysis on formation of shear band of methane hydrate bearing soils[J]. Chinese Journal of Geotechnical Engineering, 2014, 36(9): 1624-1630. (in Chinese))
[5]	蔡正银. 砂土的渐进破坏及其数值模拟[J]. 岩土力学, 2008, 29(3): 580-585. (CAI Zheng-yin. Progressive failure of sand and its numerical simulation[J]. Rock and Soil Mechanics, 2008, 29(3): 580-585. (in Chinese))
[6]	曾亚武, 黎玲, 熊俊, 等. 基于塑性体积应变的梯度塑性理论研究[J]. 长江科学院院报, 2012, 29(8): 7-11, 51. (ZENG Ya-wu, LI Ling, XIONG Jun, et al. Gradient plasticity theory based on plastic bulk strain[J]. Journal of Yangtze River Scientific Research Institute, 2012, 29(8): 7-11, 51. (in Chinese))
[7]	邵龙潭, 王助贫, 刘永禄. 三轴土样局部变形的数字图像测量方法[J]. 岩土工程学报, 2002, 24(2): 159-163. (SHAO Long-tan, WANG Zhu-pin, LIU Yong-lu. Digital image processing technique for measurement of the local deformation of soil specimen in triaxial text[J]. Chinese Journal of Geotechnical Engineering, 2002, 24(2): 159-163. (in Chinese))
[8]	唐洪祥, 董益峰, 张兴. 滚动机制对颗粒材料剪切带形成的影响[J]. 水利与建筑工程学报, 2014, 12(4): 107-111. (TANG Hong-xiang, DONG Yi-feng, ZHANG Xing. The effects of rolling resistance on the formation of shear bands for granular materials[J]. Journal of Water Resources and Architectural Engineering, 2014, 12(4): 107-111. (in Chinese))
[9]	郭莹, 王健. 基于图像测量的饱和细砂排水剪切试验研究[J]. 岩土力学, 2012, 33(1): 24-30. (GUO Ying, WANG Jian. Study of drained shear tests of saturated fine sand basedon digital image measuring[J]. Rock and Soil Mechanics, 2012, 33(1): 24-30. (in Chinese))
[10]	李元海, 朱合华, 上野胜利, 等. 基于图像相关分析砂土试验模型变形场量测[J]. 岩土工程学报, 2004, 26(1): 36-41. (LI Yuan-hai, ZHU He-hua, KATSUTOSHI U, et al. Deformation field measurement for granular soil model using image analysis[J]. Chinese Journal of Geotechnical Engineering, 2004, 26(1): 36-41. (in Chinese))
[11]	李元海, 靖洪文, 朱合华, 等. 基于图像相关分析的土体剪切带识别方法[J]. 岩土力学, 2007, 28(3): 522-526. (LI Yuan-hai, JING Hong-wen, ZHU He-hua, et al. A technique of identifying shear band accurately in granular soil using image correlation analysis[J]. Rock and Soil Mechanics, 2007, 28(3): 522-526. (in Chinese))
[12]	王学滨, 杜亚志, 潘一山, 等. 基于DIC粗-细搜索方法的单向压缩砂样的侧向变形观测研究[J]. 工程力学, 2013, 30(4): 184-190. (WANG Xue-bin, DU Ya-zhi, PAN Yi-shan, et al. Lateral deformation measurements for sand specimens under uniaxial compression based on digital image correlation with coarse-fine search method[J]. Engineering Mechanics, 2013, 30(4): 184-190. (in Chinese))
[13]	王学滨, 杜亚志, 潘一山. 单轴压缩湿砂样局部及整体体积应变的数字图像相关方法观测[J]. 岩土工程学报, 2014, 36(9): 1648-1656. (WANG Xue-bin, DU Ya-zhi, PAN Yi-shan. Measurements of local and global volumetric strains for wet sand specimens under uniaxial compression using digital image correlation method[J]. Chinese Journal of Geotechnical Engineering, 2014, 36(9): 1648-1656. (in Chinese))