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Year 2022
 
Vol 63, Issue 3a, [07 - 2022] - Full papers

Numerical analysis of the influence of coal pillar size on auxiliary tunnel stability

DOI:10.46326/JMES.2022.63(3a).09

  • Affiliations:

    Hanoi University of Mining and Geology, Hanoi, Vietnam

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  • Received: 9th-Aug-2021
  • Revised: 20th-Nov-2021
  • Accepted: 3rd-Jan-2022
  • Online: 31st-July-2022
Pages: 78 - 86
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Abstract:

It is very important to study the stability of the tunnel in the area affected by mining activities. In particular, the choice of coal pillar size has a direct influence on the stability of these tunnels. The authors of this study used the Flac3D program to model a mining face LC1 with various coal pillar sizes. The 220 m-long mining face known as LC1 has 20 degrees rock mass layers. The studied coal pillars are various widths at 5 m, 8 m, 10 m, 15 m, 20 m, and 30 m. The highest vertical stress and maximum horizontal stress are placed at different locations along the lower mining face (LC2), as shown by the results of the numerical simulation. The pressure distribution of the rock mass on the tunnel's top and the level of stress concentration on its two sides are asymmetrical for inclined seam conditions. The position of the maximum vertical tension is expected to change from the left hip to the side of the coal pillar as the coal pillar widens. This change essentially marks the system's transition from one stable state to another. Due to the rock mass's weak stability during this transition, the support must be strengthened in order to improve the rock stability.

How to Cite
Pham, N.Thi and Nguyen, C.Thi 2022. Numerical analysis of the influence of coal pillar size on auxiliary tunnel stability (in Vietnamese). Journal of Mining and Earth Sciences. 63, 3a (Jul, 2022), 78-86. DOI:https://doi.org/10.46326/JMES.2022.63(3a).09.
References

Das, A. J., Mandal, P. K., Bhattacharjee, R., Tiwari, S., Kushwaha, A., and Roy, L. B., (2017). Evaluation of stability of underground workings for exploitation of an inclined coal seam by the ubiquitous joint model. International Journal of Rock Mechanics and Mining Sciences 93, 101-114.Dao, V. D., (2016). Study to determine the size of natural protective pillar for the prepare tunnel at level -300 in Khe Cham coal mine using FLAC3D software. Mining Industrial journal, vol 5, P 53-58 (in Vietnamese)Jiang, S. J., (2015). Application of gob-side entry technology in deep high-stress coal seam mining. Coal mine safety journal, 2015 - 04 (in Chinese)Ma, Q H., Wang, Y. T., (2009). Mechanism of Narrow Pillar Protecting Roadway and Support Technology of Gob-Side Entry in Deep Mine. Journal of Mining and Safety Engineering. 2009.Men, K. H., (2000). Study on the Deformation of Narrow Pillar of Roadway DrivingAlong Next Goafof Fully mechanized Caving Face and Its Control. Doctor of Engineering, March 2000.Pham, Q. N., Tran, T. M., (2018). Studying the stability and determining the reasonable location of the preparing tunnels with steep seams conditions of underground coal mines in Quang Ninh. National Mining Science and Technology Conference, 10-11/8, Mong Cai, Quang Ninh (in Vietnamese)Sun, Y., Li, G., Zhang, J., and Qian, D., (2020). Experimental and numerical investigation on a novel support system for controlling roadway deformation in underground coal mines. Energy Science and Engineering, 8(2), 490-500.Vu, M. H., (2015). Studying the law of occurrence of mine pressure and rock deformation in mechanized tunnels of coal mine in Quang Ninh, Viet Nam. Scientific research project of the Ministry of Industry and Trade, P 105- 119 (in Vietnamese).Xie, G. X., Yang, K., Chang, J. C., (2007). Influenced of coal pillar width on deformation and fracture of gateway surrounding rocks in fully mechanized top-coal caving mining. Journal of Liaoning Technical University 26(2), 173-176.DOI：10.3969/j.issn.1008 0562.2007.02.004.Yao, G. M., Kang, L. J., (2002). Study on the chain pillar stability of the developing entry in longwall top-coal mining. Journal of China Coal Society 027(001), 6-10. DOI：10.3321/j.issn: 0253-9993.2002.01.002.Zhang, K. X., (2011). Determining the reasonable width of chain pillar of deep coal seams roadway driving along next goaf. Journal of China coal society Vol 36 Supp 1, 29-35.Zhang, K. X., Zhang, Y., Zhenqian, B. W., Yang, Y., Yang, L. I., (2015). Determination of the narrow pillar width of gob-side entry driving. Journal of Mining and Safety Engineering Vol.32 No.3, 447-452.

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