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Based on three‐dimensional digital image correlation (3D‐DIC) technique, the deformation behavior, damage and fracture characteristics of the granite specimens have been tested and observed by the short core in compression (SCC) method. The test results show that (1) the damage degree of rock in the region of interest (ROI) increases with axial stress. Before peak stress, damage factor based on apparent principal strain increases slowly, then rises rapidly; (2) relative displacements in both horizontal and vertical directions are observed, indicating that the fracture mode for SCC specimens subjected to uniaxial compression is the tensile‐shear mixed mode fracture; (3) new fracture initiates from the middle part of the expected shear fracture band (ESFB) then propagates along the loading direction. A dominant macro‐fracture, linking up the tips of two notches, eventually forms. Meanwhile, a calculation method based on the energy conservation law for the fracture energy of SCC specimens is proposed. The fracture energy of granite is estimated as 1760.4 J/m2.

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Flaws and discontinuities play a crucial role in the failure process of rocks. To investigate the fracturing mechanism of rock with combined flaws composed of crack and hole, the digital image correlation (DIC) method is used to record and analyze the rock failure behavior. Coupled static and dynamic loads are applied on granite specimens with prefabricated flaws by a modified split Hopkinson pressure bar (SHPB) device. The dynamic mechanical properties of the granite specimens are affected by the flaw inclinations with the loading directions. With the inclination angle increasing, the combined strength and peak strain both decrease first and then increase. Full- and local-field strain evolution of the granite specimens is analyzed in a quantitative way by using DIC technique. The specimens with a flaw angle of 45° are broken relatively evenly with homogenous small particle sizes. The variation trend of fragment sizes is consistent with that of combined strength and absorption energy of the specimens.

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