Displacement measurement was conducted on compact normal and shear specimens made of acrylic homogeneous material subjected to mixed-mode loading by digital image correlation. The displacement obtained by experiment is not as smooth as that obtained by finite element analysis. Therefore, displacement data were smoothed by 2-D FFT filtering and least squares method. The intelligent hybrid method proposed by Nishioka was applied to the stress-strain analysis near the crack tip. The accuracy of stress-intensity factor at the free surface was discussed from both viewpoint of experiment and 3-D finite element analysis. The surface images before and after deformation were taken by a CMOS camera, and we developed the system which enabled the real time stress analysis based on digital image correlation and inverse problem analysis. The great portion of processing time of this system was spent on displacement analysis. Then, we tried improvement in speed of this portion. In the case of cracked body, it is also possible to evaluate fracture mechanics parameters such as J integral, the strain energy release rate, and stress intensity factor of a mixed-mode.
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