ZOU Fei, LI Hai-bo, ZHOU Qing-chun, et al. Fractal features study of rock-like material damage based on gray correlation of digital images[J]. 2012, 33(3).
ZOU Fei, LI Hai-bo, ZHOU Qing-chun, et al. Fractal features study of rock-like material damage based on gray correlation of digital images[J]. 2012, 33(3).DOI:
Based on uniaxial compression tests on gypsum specimens
a series of digital images of materials are obtained during the process from damage to failure. According to the gray correlation coefficient of the digital image
the damage magnitude is built to reflect damage evolution of the material. A series of binary images of the damage evolution are obtained by image processing. The fractal and multifractal spectrum theories are adopted to describe the damage evolution on material surface. The results show that the spatial and temporal corresponding relations exist between the distribution evolution of gray correlation coefficient and the localization of surface deformation. With the increase of damage on specimen surface
the relationship between fractal dimension and strain is linear; the curve of multifractal spectrum changes from symmetric single-peak form to left concentrated form and the spectral width decreases.