Digital gradient sensing measurement applied in static fracture mechanics experiments
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摘要: 为了研究断裂力学问题中裂纹尖端区域的局部变形场和断裂特性，采用数字梯度敏感法对带有中心贯穿裂纹的有机玻璃有限宽板条进行了静态实验研究。实验过程中通过CCD记录裂纹尖端区域不同应力状态下的散斑图，对记录的散斑图进行相关运算，得到了不同应力状态下裂纹尖端周围区域内的光线偏转角，并通过偏转角对Ⅰ型裂纹的应力强度因子进行了提取。结果表明， 通过数字梯度敏感方法计算得到的应力强度因子与理论值吻合相对较好。Abstract: In order to study the local deformation field of crack tip and fracture characteristics in fracture mechanics, static fracture tests of the limited-width polymethyl methacrylate specimen with center-crack were carried out with digital gradient sensing method. Speckle patterns under different states of stress near the crack tip were recorded by CCD in the experiment. Angular deflection was obtained by digital image correlation method and stress intensity factor in mode Ⅰ crack was extracted by angular deflection. It shows that the stress intensity factor calculated by digital gradient sensing measurement method is consistent with theoretical results.
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[1] PERIASAMY C, TIPPUR H V. A full-field reflection-mode digital gradient sensing method for measuring orthogonal slopes and curvatures of thin structures [J]. Measurement Science and Technology,2013, 24(2):025202.
[2] PERIASAMY C, TIPPUR H V. Measurement of orthogonal stress gradients due to impact load on a transparent sheet using digital gradient sensing method [J]. Experimental Mechanics,2013, 53(1): 97-111.
[3] BRUCK H A, MCNEIL S R, SUTTON M A, et al. Digital image correlation using Newton-Raphson method of partial differential correction [J]. Experimental Mechanics, 1989, 29(3):261-267.
[4] PETERS W H, RANSON W F. Digital imaging techniques in experimental stress analysis [J]. Optical Engineering, 1981, 21(3):427-431.
[5] CHU T C, RANSON W F, SUTTON M A, et al. Applications of digital-image-correlation techniques to experimental mechanics [J]. Experimental Mechanics,1985, 25(3): 232-244.
[6] YU H, GUO R X, XIA H T, et al. Experimental study on the elastic modulus of WC/Cu composite material with different WC content [J]. Laser Technology, 2013, 37(2): 140-143(in Chin-ese).
[7] PERIASAMY C, TIPPUR H V. A full-field digital gradient sensing method for evaluating stress gradients in transparent solids [J]. Applied Optics,2012, 51(12): 2088-2097.
[8] TIPPUR H V, KRISHNASWAMY S, ROSAKIS A J. Optical mapping of crack tip deformations using the methods of transmission and reflection coherent gradient sensing-a study of crack tip K-dominance [J]. International Journal of Fracture, 1991,52(2):91-117.
[9] YAO X F,YU W, LIU D L, et al. Coherent gradient sensing interferometry technology and its application [J]. Journal of Experimental Mechanics,2006, 21(5):560-564(in Chinese).
[10] SCHREIER H W, SUTTON M A. Systematic errors in digital image correlation due to undermatched subset shape functions [J]. Experimental Mechanics,2002, 42(3):303-310.
[11] LI Q F, LI S F. Fracture mechanics and its application in engineering [M].Harbin: Harbin Engineering University Press,2008: 29-253(in Chinese).
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