Measurement of Shear Band Widths Based on the Digital Image Correlation Method Considering Splitted Subsets Surrounding the Monitored Point
ZHANG Bo-wen1, WANG Xue-bin1,2, DONG Wei1
1. College of Mechanics and Engineering, Liaoning Technical University, Fuxin, Liaoning 123000, China
2. Institute of Computational Mechanics, Liaoning Technical University, Fuxin, Liaoning 123000, China
Abstract:To accurately measure widths of narrow shear bands with high strain gradients, a new digital image correlation method was proposed based on the subset splitting . Through splitting the original subset of the monitored point, and making splitted subsets surround the point, a few splitted subsets were in simple deformational regions. Results of the best correlated subsets were taken as results of the point. The validity of the proposed method was verified by comparing measured fictitious shear band widths of the proposed method and the coarse-fine method, and shear band width measurement errors of two methods were analyzed in theory. It is shown that the measured fictitious shear band widths of the proposed method are not influenced by the subset size in theory. Measured shear band widths of the proposed method are less influenced by the subset size and more influenced by the monitored point spacing than of the coarse-fine method. Measured shear band widths of the proposed method are more accurate than of the coarse-fine method.
张博闻, 王学滨, 董伟. 基于环绕测点子区分割的数字图像相关方法剪切带宽度测量研究[J]. 计量学报, 2022, 43(1): 40-47.
ZHANG Bo-wen, WANG Xue-bin, DONG Wei. Measurement of Shear Band Widths Based on the Digital Image Correlation Method Considering Splitted Subsets Surrounding the Monitored Point. Acta Metrologica Sinica, 2022, 43(1): 40-47.
[1] 资新运, 耿帅, 赵姝帆, 等. 3种亚像素位移测量算法的比较研究[J]. 计量学报, 2015, 36(3): 260-267.
Zi X Y, Geng S, Zhao S F, et al. Comparison of three sub-pixel displacement algorithm[J]. Acta Metrologica Sinica, 2015, 36(3): 260-267.
[2] 王学滨, 侯文腾, 董伟, 等. 基于局部位移场最小二乘拟合数字图像相关方法的剪切带应变测量[J]. 计量学报, 2019, 40(4): 655-661.
Wang X B, Hou W T, Dong W, et al. Strain measurements of shear bands based on least-square fitting of local displacements based on the digital image correlation method[J]. Acta Metrologica Sinica, 2019, 40(4): 655-661.
[3] 庄丽, 宫全美. 减围压平面应变压缩试验条件下丰浦砂中剪切带特性研究[J]. 岩土力学, 2016, 37(S1): 201-208.
Zhuang L, Gong Q M. Shear band characteristics of Toyoura sand in plane strain compression with decreasing confining pressure[J]. Rock and Soil Mechanics, 2016, 37(S1): 201-208.
[4] 杜亚志, 王学滨, 董伟, 等. 基于一阶及二阶DIC方法的常应变剪切带的测量误差分析[J]. 计量学报, 2018, 39(1): 66-71.
Du Y Z, Wang X B, Dong W, et al. Analyses of measurement errors of shear bands with constant strains based on the One-and Two-order DIC methods[J]. Acta Metrologica Sinica, 2018, 39(1): 66-71.
[5] Nübel K. Experimental and numerical investigation of shear localization in granular material[R]. Karlsruhe: University of Karlsruhe, 2002.
[6] 王学滨, 董伟, 侯文腾, 等. 基于背景值及数字图像相关方法的土样剪切带宽度测量[J]. 西北农林科技大学学报(自然科学版), 2018, 46(12): 147-154.
Wang X B, Dong W, Hou W T, et al. Measurement of shear band widths of clay specimen based on background value method and digital image correlation method[J]. Journal of Northwest A & F University (Natural Science Edition), 2018, 46(12): 147-154.
[7] 李元海, 林志斌, 靖洪文, 等. 含动态裂隙岩体的高精度数字散斑相关量测方法[J]. 岩土工程学报, 2012, 34(6): 1060-1068.
Li Y H, Lin Z B, Jing H W, et al. High-accuracy digital speckle correlation method for rock with dynamic fractures[J]. Chinese Journal of Geotechnical Engineering, 2012, 34(6): 1060-1068.
[8] Jin H, Bruck H A. Pointwise digital image correlation using genetic algorithms[J]. Experimental Techniques, 2005, 29(1): 36-39.
[9] Réthoré J, Hild F, Roux S. Shear-band capturing using a multiscale extended digital image correlation technique[J]. Computer Methods in Applied Mechanics and Engineering, 2007, 196(49-52): 5016-5030.
[10] Poissant J, Barthelat F. A novel “subset splitting” procedure for digital image correlation on discontinuous displacement fields[J]. Experimental Mechanics, 2010, 50(3): 353-364.
[11] 杜亚志, 王学滨, 董伟. 修正的子区分割法及剪切带的位移和应变的测量[J]. 光学技术, 2018, 44(2): 158-163.
Du Y Z, Wang X B, Dong W. An improved subset splitting method and applications into the measurements of displacements and strains of shear bands[J]. Optical Technology, 2018, 44(2): 158-163.
[12] Zhou P, Goodson K E. Subpixel displacement and deformation gradient measurement using digital image/speckle correlation[J]. Optical Engineering, 2001, 40(8): 1613-1621.
[13] 王学滨, 潘一山, 马瑾. 剪切带内部应变(率)分析及基于能量准则的失稳判据[J]. 工程力学, 2003, 20(2): 111-115.
Wang X B, Pan Y S, Ma J. Analysis of strain (or the ratio of strain) in the shear band and a criterion on instability based on the energy criterion[J]. Engineering Mechanics, 2003, 20(2): 111-115.
[14] 王学滨, 董伟, 杨梅, 等. 基于最小一乘拟合的非均匀应变的数字图像相关测量[J]. 光学学报, 2020, 40(3): 65-73.
Wang X B, Dong W, Yang M, et al. Inhomogeneous strain measurement based on least absolute deviation fitting for digital image correlation[J]. Acta Optica Sinica, 2020, 40(3): 65-73.
[15] 徐小海, 苏勇, 蔡玉龙, 等. 数字图像相关法测量局域变形场中形函数和模板尺寸的影响[J]. 力学学报, 2015, 47(5): 848-862.
Xu X H, Su Y, Cai Y L, et al. Influence of shape functions and template size in digital image correlation method for highly inhomogeneous deformations[J]. Chinese Journal of Theoretical and Applied Mechanics, 2015, 47(5): 848-862.