| Autor: |
Yiqiang Kang, Renshu Yang, Liyun Yang, Chengxiao Li, Jun Chen, Haonan Zhu, Ning Liu |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
International Journal of Mining Science and Technology, Vol 33, Iss 7, Pp 815-828 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
2095-2686 |
| DOI: |
10.1016/j.ijmst.2023.03.006 |
| Popis: |
A plane mechanical model of rock breaking process by double disc cutter at the center of the cutterhead is established based on contact mechanics to analyze the stress evolution in the rock broken by cutters with different spacings. A continuous-discontinuous coupling numerical method based on zero-thickness cohesive elements is developed to simulate rock breaking using double cutters. The process, mechanism, and characteristics of rock breaking are comprehensively analyzed from five aspects: peak force, breaking form, breaking efficiency, crack mode, and breaking degree. The results show that under the penetrating action of cutters, dense cores are formed due to shear failure under respective cutters. The tensile cracks propagate in the rock, and then rock chips form with increasing penetration depth. When the cutter spacing is increased from 10 to 80 mm, the peak force gradually increases, the rock breaking range increases first and then decreases, the specific energy decreases first and then rises, and the breaking coefficient of intermediate rock decreases from 0.955 to 0.788. The area of rock breaking is positively correlated with the length of the tensile crack. Furthermore, the length of the tensile crack accounts for 14.4%–33.6% of the total crack length. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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