Geomechanics and Engineering

  • 제18권2호
  • /
  • Pages.111-119
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  • 2019
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  • 2005-307X(pISSN)
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  • 2092-6219(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

Influence of explosives distribution on coal fragmentation in top-coal caving mining

  • Liu, Fei (School of Energy and Mining Engineering, China University of Mining & Technology) ;
  • Silva, Jhon (Department of Mining Engineering, University of Kentucky) ;
  • Yang, Shengli (School of Energy and Mining Engineering, China University of Mining & Technology) ;
  • Lv, Huayong (School of Energy and Mining Engineering, China University of Mining & Technology) ;
  • Zhang, Jinwang (School of Energy and Mining Engineering, China University of Mining & Technology)
  • 투고 : 2019.04.01
  • 심사 : 2019.05.08
  • 발행 : 2019.06.10
⟨ 이전 논문 다음 논문 ⟩

초록

Due to certain geological characteristics (high thickness, rocky properties), some underground coal mines require the use of explosives. This paper explores the effects of fragmentation of different decks detonated simultaneously in a single borehole with the use of numerical analysis. ANSYS/LS-DYNA code was used for the implementation of the models. The models include an erosion criterion to simulate the cracks generated by the explosion. As expected, the near-borehole area was damaged by compression stresses, while far zones and the free surface of the boundary were subjected to tensile damage. With the increase of the number of decks in the borehole, different changes in the fracture pattern were observed, and the superposition effects of the stress wave became evident, affecting the fragmentation results. The superposition effect is more evident in close distances to the borehole, and its effect attenuates when the distance to the borehole increase.

키워드

과제정보

연구 과제 주관 기관 : National Natural Science Foundation of China

참고문헌

  1. Alehossein, H. and Poulsen, B.A. (2010), "Stress analysis of longwall top coal caving", Int. J. Rock Mech. Min. Sci., 47(1), 30-41. https://doi.org/10.1016/j.ijrmms.2009.07.004.
  2. Azam, S. and Mishra, D.P. (2019), "Effects of particle size, dust concentration and dust-dispersion-air pressure on rock dust inertant requirement for coal dust explosion suppression in underground coal mines", Proc. Safety Environ. Protect. https://doi.org/10.1016/j.psep.2019.03.030.
  3. Gasparotto, J., Chaves, P.R., Da Boit Martinello, K., da Rosa-Siva, H.T., Bortolin, R.C., Silva, L.F.O., Rabelo, T.K., da Silva, J., da Silva, F.R., Nordin, A.P., Soares, K., Borges, M.S., Gelain, D.P. and Moreira, J.C.F. (2018), "Obese rats are more vulnerable to inflammation, genotoxicity and oxidative stress induced by coal dust inhalation than non-obese rats", Ecotoxicol. Environ. Safety, 165, 44-51. https://doi.org/10.1016/j.ecoenv.2018.08.097.
  4. Greene, N.T., Alhussaini, M.A., Easter, J.R., Argo IV, T.F., Walilko, T. and Tollin, D.J. (2018), "Intracochlear pressure measurements during acoustic shock wave exposure", Hear. Res., 365, 149-164. https://doi.org/10.1016/j.heares.2018.05.014
  5. Hao, H. (2002), "Numerical analysis of blast-induced stress waves in a rock mass with anisotropic continuum damage models part 1: Equivalent material property approach", Rock Mech. Rock Eng., 35(2), 79-94. https://doi.org/10.1007/s006030200012
  6. Headquarters, U.S. Army Corps of Engineers (1995), "Underwater Blast Monitoring", Engineer Technical Letter No. 1110-8-11,
  7. U.S. Army Corps of Engineers, Washington, D.C., U.S.A. Houim, R.W. and Oran, E.S. (2015), "Numerical simulation of dilute and dense layered coal-dust explosions", Proc. Combust. Inst., 35(2), 2083-2090. https://doi.org/10.1016/j.proci.2014.06.032.
  8. Konicek, P., Soucek, K., Stas, L. and Singh, R. (2013), "Long-hole destress blasting for rockburst control during deep underground coal mining", Int. J. Rock Mech. Min. Sci., 61, 141-153. https://doi.org/10.1016/j.ijrmms.2013.02.001.
  9. Le, T.D., Mitra, R., Oh, J. and Hebblewhite, B. (2017), "A review of cavability evaluation in longwall top coal caving", Int. J. Min. Sci. Technol., 27(6), 907-915. https://doi.org/10.1016/j.ijmst.2017.06.021.
  10. Lee, E.L., Hornig, H.C. and Kury, J.W. (1968), "Adiabatic expansion of high explosive detonation products", Report UCRL-50422, University of California, Lawrence Radiation Laboratory, Livermore, California, U.S.A.
  11. Li, N., Huang, B., Zhang, X., Yuyang, T. and Li, B. (2019), "Characteristics of microseismic waveforms induced by hydraulic fracturing in coal seam for coal rock dynamic disasters prevention", Safe. Sci., 115, 188-198. https://doi.org/10.1016/j.ssci.2019.01.024.
  12. Livermore Software Technology Corporation (LSTC), (2003), LSDYNA Keyword User's Manual, Version 970. Livermore, California, U.S.A.
  13. Mondal, D. and Roy, P.N.S. (2019), "Fractal and seismic b-value study during dynamic roof displacements (roof fall and surface blasting) for enhancing safety in the longwall coal mines", Eng. Geol., 253,184-204. https://doi.org/10.1016/j.enggeo.2019.03.018.
  14. Ozacar, V. (2018), "New methodology to prevent blasting damages for shallow tunnel", Geomech. Eng., 15(6), 1-12. https://doi.org/10.12989/gae.2018.15.6.001.
  15. Saiang, D. (2009), "Stability analysis of the blast-induced damage zone by continuum and coupled continuum-discontinuum methods", Eng. Geol., 116, 1-11. https://doi.org/10.1016/j.enggeo.2009.07.011.
  16. Sampath, K.H.S.M., Perera, M.S.A., Elsworth, D., Ranjith, P.G., Matthai, S.K., Rathnaweera, T. and Zhang, G. (2019), "Effect of coal maturity on CO2-based hydraulic fracturing process in coal seam gas reservoirs", Fuel, 236, 179-189. https://doi.org/10.1016/j.fuel.2018.08.150.
  17. Sanchidrian, J.A., Castedo, R., Lopez, L.M. and Segarra, P. and Santos, A.P. (2015), "Determination of the JWL constants for ANFO and emulsion explosives from cylinder test data", Cent. Eur. J. Energ. Mater., 12(2), 177-194.
  18. Sharma, S.K. and Rai, P. (2017), "Establishment of blasting design parameters influencing mean fragment size using state-of-art statistical tools and techniques", Measurement, 96, 34-51. https://doi.org/10.1016/j.measurement.2016.10.047.
  19. Silva, J., Li, L. and Gernand, J.M. (2018), "Reliability analysis for mine blast performance based on delay type and firing time", Int. J. Min. Sci. Technol., 28(2), 195-204. https://doi.org/10.1016/j.ijmst.2017.07.004.
  20. Thiagarajan, G., Kadambi, A.V., Robert, S. and Johnson, C.F. (2015), "Experimental and finite element analysis of doubly reinforced concrete slabs subjected to blast loads", Int. J. Impact Eng., 75, 162-173. https://doi.org/10.1016/j.ijimpeng.2014.07.018.
  21. Timo, S. (2010), "Damage-viscoplastic consistency model with a parabolic cap for rocks with brittle and ductile behavior under low-velocity impact loading", Int. J. Numer. Anal. Meth. Geomech., 34, 1362-1386. https://doi.org/10.1002/nag.868.
  22. Vakili, A. and Hebblewhite, B.K. (2010), "A new cavability assessment criterion for Longwall Top Coal Caving", Int. J. Rock Mech. Min. Sci., 47(8), 1317-1329. https://doi.org/10.1016/j.ijrmms.2010.08.010.
  23. Wang, J.C., Liu, F. and Zhang, J.W. (2019), "Investigation on the propagation mechanism of explosion stress wave in underground mining", Geomech. Eng., 17(3), 295-305. https://doi.org/10.12989/gae.2019.17.3.295.
  24. Wang, X.L. and Suo, Y.L. (1995), "Computer simulation of preexplosion of fully mechanized coal caving roof in hard coal seam", J. Xi'an. Min. Inst., 15, 97-101.
  25. Wang, Z.L. (2007), "Numerical simulation of tensile damage and blast crater in brittle rock due to underground explosion", Int. J. Rock Mech. Min. Sci., 44(5), 730-738. https://doi.org/10.1016/j.ijrmms.2006.11.004.
  26. Wojtecki, L., Konicek, P. and Schreiber, J. (2017), "Effects of torpedo blasting on rockburst prevention during deep coal seam mining in the Upper Silesian Coal Basin", J. Rock Mech. Geotech. Eng., 9(4), 694-701. https://doi.org/10.1016/j.jrmge.2017.03.014.
  27. Wojtecki, L., Konicek, P., Mendecki, M.J. and Zuberek, W.M. (2017), "Application of seismic parameters for estimation of destress blasting effectiveness", Proc. Eng., 191, 750-760. https://doi.org/10.1016/j.proeng.2017.05.241.
  28. Xie, L.X., Lu, W.B. and Zhang, Q.B. (2016), "Damage evolution mechanisms of rock in deep tunnels induced by cut blasting", Tunn. Undergr. Sp. Technol., 58, 257-270. https://doi.org/10.1016/j.tust.2016.06.004.
  29. Xu, B. (2004), "Application of the longwall top coal caving system in Australian thick seam coal mines", The University of New South Wales, Sydney, Australia.

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