ABSTRACT
Dynamic compressive parameters of coal specimens were driven not only by impact velocities, but also by preloaded confining pressure, and impact loading methods. This paper investigates the influences of dynamic parameters based on the split Hopkinson pressure bar (SHPB) experimental data obtained from the dynamic compressive impact tests on 12 coal specimens under four different impact velocity. The analysis of the experimental results confirmed that with an increase of dynamic velocity, and then the dynamic compressive strength is constantly increases. When the dynamic velocity is 8.10 m/s, and then reacheed the maximum dynamic strength of 25.11 MPa of the coal specimen. Furthermore, the dynamic velocity of 8.10 m/s was defined as the threshold value of the dynamic strength increased. The greater of dynamic velocity, the higher degree of fragmentation of the coal specimens. The transmitted energy, reflected energy, and absorbed energy of coal specimens shows a directly proportional relationship with the incident energy. The results highlight the first and second dynamic deformation moduli can clearly explained the deformation laws of elastic and plastic stages of the coal specimens. It is also found that the maximum of strain rate is 177.28 s−1 and the maximum ultimate strain is 2.47 × 10−2of the coal specimens. The research results were beneficial to supplement the coal-rock dynamics theory, thus also providing a direction for safety and effective mining and crushing in coal mines.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Authors contributions
Han Meng – Writing original draft, Investigation. Yuzhong Yang: Writing, review & editing. Wei Hou: Investigation. Xinwang Li – Funding acquisition. Li Chen – Methodology & Conceptualization. Daming Yang – Conceptualization, Methodology. Chenlin Wang – Review & editing. Longlong Pang – Formal analysis, Validation.
Additional information
Funding
Notes on contributors
Han Meng
Han Meng mainly engaged in original draft and investigation
Yuzhong Yang
Yuzhong Yang mainly engaged in review and editing
Wei Hou
Wei Hou mainly engaged in investigation
Xinwang Li
Xinwang Li mainly in analysis and technology research
Li Chen
Li Chen mainly engaged in methodology and conceptualization
Daming Yang
Daming Yang mainly engaged in conceptualization and methodology
Chenlin Wang
Chen Lin Wang mainly engaged in review
Longlong Pang
Longlong Pang mainly engaged in formal analysis and validation