Improved extended digital image correlation for crack tip deformation measurement

• DOI: 10.1016/j.optlaseng.2014.06.010
• Publication Date: 2014-07-04T16:30:20Z
• Authors: Jinlong Chen; Nan Zhan; Xiaochuan Zhang; Jixiao Wang
• Keywords: Digital image correlation

Abstract The objective is to find an appropriate shape function which can enhance the performance of Extended Digital Image Correlation (X-DIC). This paper presents an improved X-DIC methodology to measure the discontinuous deformation across the crack. After simplifying the shape function of crack tip element based on the linear elastic fracture mechanics, non-rectangular subset is proposed to eliminate the effect of the crack width on the measurement accuracy. Then, the work verifies the performance of improved X-DIC by measuring the deformation of a specimen with a mode I crack. Experimental results show that the proposed method is effective at improving the measurement accuracy and enhancing the computational efficiency of X-DIC. In the end, the thesis provides a practical application of improved X-DIC to crack tip deformation measurement.