Abstract
A 3D particle-based numerical approach to simulate the longwall top coal caving (LTCC) process was proposed, which for the first time the effect of continuous support advance and the face-end support were considered. The shape of drawing body and top coal boundary and the distribution characteristics of coal loss were analysed. The top coal flow trajectories and velocity fields were visualized and consistent with the assumptions in Bergmark-Roos model. The vertical forces on the drawing support beams were continuously monitored during the process of simulation. It was found that both the drawing procedure and the support advance will lead to a reduction of the vertical forces on support beams. Results of the numerical simulations and laboratory testing were compared and good consistency was obtained.
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Abbreviations
- BC:
-
Block caving
- B-R model:
-
Bergmark-Roos model
- DO:
-
Drawing opening
- DS:
-
Drawing support
- FS:
-
Face-end support
- LTCC:
-
Longwall top coal caving
- PFC:
-
Particle flow code
- IEZ:
-
Isolated extracted zone
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Acknowledgements
The authors would like to express their thanks to the Chinese Scholarship Council (CSC) on behalf of financial funding for the first author’s study and living in Germany. The authors would like to acknowledge Dr. Martin Herbst from TU Bergakademie Freiberg for his guidance. The authors also want to acknowledge all the reviewers and editors for their contributions to improve the manuscript.
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Song, Z., Konietzky, H. A particle-based numerical investigation on longwall top coal caving mining. Arab J Geosci 12, 556 (2019). https://doi.org/10.1007/s12517-019-4743-z
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DOI: https://doi.org/10.1007/s12517-019-4743-z