13th International Conference on Fracture June 16–21, 2013, Beijing, China -8- Table 1: Isotropic case b Force (N) K1 (ε) (m1/2) K2 (ε) (m1/2) K1 (σ) (MPa⋅m1/2) K2 (σ) (MPa⋅m1/2) G1 (J/m²) G2 (J/m²) 0° 1515 5.03⋅10-3 0 1.63 0 1025 0 15° 1535 2.04⋅10-3 3.44⋅10-4 0.66 0.11 168 5 45° 1571 2.34⋅10-3 9.80⋅10-4 0.76 0.32 222 39 75° 1545 5.49⋅10-4 9.51⋅10-4 0.18 0.31 10 37 Table 2: Orthotropic case b Force (N) K1 (ε) (m1/2) K2 (ε) (m1/2) K1 (σ) (MPa⋅m1/2) K2 (σ) (MPa⋅m1/2) G1 (J/m²) G2 (J/m²) 0° 245 2.08⋅10-3 0 0.45 0 116 0 15° 277 5.95⋅10-4 1.43⋅10-4 0.14 0.11 10.5 2.02 45° 748 1.35⋅10-3 7.43⋅10-4 0.32 0.59 54 55.2 75° 876 6.91⋅10-4 6.58⋅10-4 0.16 0.52 14.2 42.9 4. Conclusion This work has presented an original coupling between Digital Image Correlation and Finite Element Analysis, making it possible to characterize both the mechanical and energy states in the crack tip vicinity. Based on Dubois' developments, the kinematic state in the crack tip vicinity is evaluated using the Crack Relative Displacement Factors calculated from experimental measurements output by DIC. In parallel with this step, the stress distribution is evaluated by a finite element analysis according to the Mq method. The coupling of these two approaches allows distinguishing and calculating the energy release rates corresponding to opening and shear modes. The originality of this coupling procedure lies in the possibility of calculating the energy release rate independently of material elastic properties. Furthermore, our formalism allows evaluating local elastic properties via the elastic compliance correlated with Crack Relative Displacement Factors and Stress Intensity Factors. In terms of follow-up work, crack initiation and propagation can be studied in greater depth thanks to this new technique, thus leading to a better understanding of all phenomena governing the crack tip growth process. References [1] B. Budiansky, J.R Rice, Conservation laws and energy release rate. Journal of Applied Mechanics, 400 (1973) 201-203. [2] A.G. Hermann, On energy release rates for a plane crack. Journal of Applied Mechanics, 48, (1981) 525-528. [3] L.B. Freund, Stress-intensity factor calculations based on a conservation integral. International of Journal of Solids and Structures, 14 (1978) 241-250. [4] J.H. Chang, A.J. Chien, Evaluation of M-integral for anisotropic elastic media with multiple
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