In this paper, mesoscopic parameters of sandstone are obtained by SEM and image processing, and mechanical parameters of sandstone are obtained by uniaxial compression experiment, based on which the PFC^2D model of red sandstone is established. Through numerical simulation of uniaxial compression, crack propagation of sandstone was observed, and parameters such as stress-strain curve and number of bond fractures were obtained. Fractal dimension of sandstone was calculated by MATLAB, and the relationship between damage degree, fractal dimension and crack propagation was analyzed. The results show that the crack development of sandstone can be divided into four stages: elastic deformation, crack initiation, crack propagation and penetration. The damage degree corresponds to each stage of fracture development, the minimum is in elastic deformation stage, and the maximum is in penetrating stage. The fractal dimension changes differently in each stage, and shows an increasing trend in the germination stage. In the expansion stage, it shows a downward trend. At the through-through stage, there is a substantial growth trend. Therefore, the box dimension can be used to indirectly evaluate the internal damage and study the damage evolution characteristics, which provides a new idea for studying the damage evolution of sandstone and has important significance for evaluating the stability of engineering rock mass.

Yingying Zhu. PFC2D numerical simulation of sandstone damage evolution based on MATLAB image processing. Academic Journal of Computing & Information Science (2023), Vol. 6, Issue 2: 120-126. https://doi.org/10.25236/AJCIS.2023.060216.

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