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| Strain Measurements of Shear Bands Based on Least-square Fitting of Local Displacements Based on the Digital Image Correlation Method |
| WANG Xue-bin1,2,HOU Wen-teng2,DONG Wei2,YANG Mei3,CAO Si-wen2 |
1. Institute of Computational Mechanics, Liaoning Technical University, Fuxin, Liaoning 123000, China
2. College of Mechanics and Engineering, Liaoning Technical University, Fuxin, Liaoning 123000, China
3. School of Mechanical Engineering, Liaoning Technical University, Fuxin, Liaoning 123000, China |
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Abstract Strains in the fictitious shear band are measured by use of least-square fitting of local displacements of the digital image correlation method, and strains are compared with those obtained by use of the central difference method and the analytical solution. Effects of the size of the calculating window and the size of the subset are mainly demonstrated. It is found that when the calculating window is larger and the size of the subset is lower, strains are closer to the analytical solution. Strains during the failure process of the low liquid-limit clay specimen under uniaxial compression are measured by use of least-square fitting of local displacements method and the central difference method, and strains are measured by least-square fitting of local displacements method are more accurate, which is helpful for the accurate measurement of strains of shear bands.
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Received: 21 September 2017
Published: 10 June 2019
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2019, Vol. 40 
