Split Hopkinson pressure bar test and cell model of the damage threshold of siltstone

• Published in: IOP conference series. Earth and environmental science Vol. 861; no. 4; pp. 42060 - 42067
• Main Authors: Zhang, Qingcheng, Liu, Dianshu
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.10.2021
• Subjects: Cell culture; Damage accumulation; Damage assessment; Damage evolution; Damage threshold; Evolution; Impact damage; Impact tests; Model testing; Renormalization group method; Self-similarity; Siltstone; Similarity theory; Split Hopkinson pressure bars; Stress waves; Tectonics; Yield point
• ISSN: 1755-1307; 1755-1315
• DOI: 10.1088/1755-1315/861/4/042060

Study the damage threshold of siltstone, we conducted the large-diameter series of split Hopkinson pressure bar cyclic impact tests on siltstone samples. When the damage value of siltstone was 0.16-0.4, increased exponentially with an increase in stress wave amplitude. Damage evolution in siltstone obeys the power-law distribution. This feature is consistent with the self-similarity theory in fractal mechanics. Thus, self-organized criticality theory can be used to determine the rock damage threshold. Combined with the microscopic tectonic features of siltstone, a 2 × 3 cell model was established by based on the renormalization group method, and the failure probability of seven 2 × 3 cell models was established by combining the force transfer coefficients among cell units. The seven damage models, showed that the damage accumulation threshold of siltstone without damage is 0.119, and the damage threshold during failure is 0.4, which is consistent with the SHPB test results. Thus, the cellular model established based on the renormalization group method can be used to study the damage evolution of siltstone.