Experimental study on the progressive failure of double‐flawed granite samples subjected to impact loads

Abstract In this paper, the split Hopkinson pressure bar device and high‐speed camera system are applied to carry out the impact tests of fine‐grained granite samples with two parallel preexisting flaws, whose angles are 0°, 15°, 30°, 45°, 60°, 75°, and 90°. The dynamic compressive strength of the double‐flawed granite samples is affected by the flaw angle. By analyzing the experimental results, the peak strengths of the double‐flawed granite samples are in low level when the flaw angles are varying from 45° to 75°, while the peak strengths of the double‐flawed granite samples are in high level when the flaw angles are in the ranges of 0°–30° and 75°–90°. The strain concentration factor is investigated based on the digital image correlation technology. Moreover, the mechanical properties, energy absorption, cracking behaviors, failure modes, and the progressive failure mechanism of the double‐flawed granite samples under impact loads are revealed.