Journal of Korean Tunnelling and Underground Space Association (한국터널지하공간학회 논문집)

Korean Tunnelling and Underground Space Association (한국터널지하공간학회)
권호 표지
DOI QR코드

DOI QR Code

A study on conceptual evaluation of structural stability of room-and-pillar underground space

주방식 지하공간의 구조적 안정성 평가개념 정립에 관한 연구

  • Lee, Chulho (Geotechnical Engineering Research Division, SOC Research Institute, Korea Institute of Construction Technology) ;
  • Chang, Soo-Ho (Geotechnical Engineering Research Division, SOC Research Institute, Korea Institute of Construction Technology) ;
  • Shin, Hyu-Soung (Geotechnical Engineering Research Division, SOC Research Institute, Korea Institute of Construction Technology)
  • 이철호 (한국건설기술연구원 SOC성능연구소 Geo-인프라연구실) ;
  • 장수호 (한국건설기술연구원 SOC성능연구소 Geo-인프라연구실) ;
  • 신휴성 (한국건설기술연구원 SOC성능연구소 Geo-인프라연구실)
  • Received : 2013.11.01
  • Accepted : 2013.11.08
  • Published : 2013.11.30
Download PDF
⟨ Previous Next ⟩

Abstract

In this study, in order to evaluate stability of the room-and-pillar underground structure, a series of preliminary numerical analyses were performed. Design concept and procedure of an underground structure for obtaining a space are proposed, which should be different from structural design for the room-and-pillar in mine. With assumed material properties, a series of numerical analyses were performed by varying size ratios of room and pillar and then the failure modes and location at yielding initiation were investigated. From the results, relationship between the ratio of pillar width to the roof span (w/s) and overburden pressure at failure initiation shows a relatively linear relation, and the effect of w/s on structural stability is much more critical than the ratio of pillar width and height (w/H) which is a crucial parameter in design of the room-and-pillar mining. It means that roof tensile failure and shear failure at shoulder and pillar are necessary to be considered together for confirming overall structural stability of the room-and-pillar structure, rather than considering the pillar stability only in mining. Failure modes and location at failure initiation were varied with respect to the ratio of room and pillar widths. Therefore, it is necessary to simultaneously consider stability of both roof span and pillar for design of underground structure by the room-and-pillar method.

본 연구에서는 주방식 지하구조물의 안정성 검토방안을 마련하기 위해 암주와 천장부의 거동을 수치해석 방법으로 검토하였다. 또한, 기존 자원개발 분야에서 고려하는 주방식 공법의 설계 개념과는 달라져야 하는, 공간 확보차원에서의 합리적인 주방식 공법의 설계 절차 및 개념을 제시하였다. 주어진 지반 조건에서 암주의 형상비와 천장부의 길이에 따른 수치해석을 수행하였으며 초기 이완이 시작되는 시점에서의 파괴유형과 위치 변화를 검토하였다. 해석결과, 천장부 폭과 암주 폭과의 비(w/s)와 파괴시점의 상재하중간의 관계는 선형관계를 보였으며, 천장부 폭과 암주 폭의 비가 주방식 채광 설계에서는 매우 중요한 설계인자로 다루어지는 암주의 폭과 높이 비(w/H)보다 구조물의 안정성 확보차원에서는 더욱 민감한 설계인자인 것으로 나타났다. 이는, 암주의 안정성 만을 확보하는 차원에서 수행되는 주방식 채광 설계법과는 달리, 암주부와 함께 구조물 천장부 및 어깨부의 안정성까지도 함께 고려하여 지하구조물의 안정성을 확보할 수 있는 구조물 설계가 되어야 함을 의미한다. 또한, 지하구조물의 형상에 따라 초기 이완대가 발생하는 위치와 전단 또는 인장파괴 등 파괴유형도 다르게 나타나, 주방식 지하구조물에 대한 설계는 상재하중에 따른 천장부와 암주의 안정성을 연계하여 수행하는 것이 필요하다.

Keywords

References

  1. Carmody, J., Sterling, R. (1993), "Underground space design - A guide to subsurface utilization and design for people in underground spaces", International Thomson Publishing company, p. 110.
  2. Dolinar, D.R. (2003), "Variation of horizontal stresses and strains in mines in bedded deposits in the eastern and midwestern united states", Proceedings of 22nd International Conference on Ground Control in Mining, Morgantown, WV, Aug. 5-7, pp. 178-185.
  3. Esterhuizen, G.S. (2006), "Evaluation of the strength of slender pillars", Trans Soc Min Explor Geol 320, pp. 69-76.
  4. Esterhuizen, G.S., Dolinar, D.R., Ellenberger, J.L. (2008a), "Pillar strength and design methodology for stone mines", In: Proceedings of the 27th international conference on ground control in mining. Morgantown WV: West Virginia University, pp. 241-253.
  5. Esterhuizen, G.S., Dolinar, D.R., Iannacchione, A.T. (2008b), "Field observations and numerical studies of horizontal stress effects on roof stability in US limestone mines", Journal of the South African Institute of Mining and Metallurgy, Vol. 108, No. 6, pp 345-352.
  6. Esterhuizen, G.S., Dolinar, D.R., Ellenberger, J.L, Prosser, L.J. (2011), "Pillar and roof span design guidelines for underground stone mines", Department of Health And Human Services, NIOSH, IC 9526.
  7. Gonzalez-Nicieza, C., Alvarez-Fernadez, M.I., Menendez-Diaz, A., Alvarez-Vigil, A.E. (2006), "A comparative analysis of pillar design methods and its application to marble mines", Rock Mech. Rock Engng., Vol. 39, No. 5, pp. 421-444. https://doi.org/10.1007/s00603-005-0078-z
  8. Hardy, P., Agapito, J.F.T. (1982), "Induced horizontal stress method of pillar design in oil shale", XV Oil Shale Symp. Colorado School of Mines, Golden, Colorado.
  9. Hartman, H.L., Mutmansky, J.M. (2002), Introductory Mining Engineering, 2nd edtion, Wiley, New Jersey.
  10. Hedley, D.G.F., Grant, F. (1972), "Stope-and-pillar design for the elliot lake uranium mines", Bull. Can. Inst. Min. Metallurg. Vol. 63, pp. 37-44.
  11. Hoek, E., Brown, E.T. (1980), Underground excavation in rock, Institution of Mining and Metallurgy.
  12. Iannacchione, A.T., Marshall, T.E., Burke, L., Melville, R., Litsenberger, J. (2003) "Safer mine layouts for underground stone mines subjected to excessive levels of horizontal stress", Mining Engineering, Vol. 55, No. 4, pp. 25-31.
  13. Kimmelmann, M.R., Hyde, B., Madgwick, R.J. (1984), "The use of computer applications at BCL limited in planning pillar extraction and design of mining layouts", In: Proc., ISMR Symp. Design and Performance of Underground Excavations. Brit. Geotech. Soc., London, pp. 53-63.
  14. Krauland, N., Soder, P.E. (1987), "Determinating pillar strength from pillar failure observations", Eng. Min. J. Vol. 8, pp. 34-40.
  15. Lee, C., Chang, S-H, Shin, H-S, (2013), "A numerical study on evaluation of unsupported pillar strength in the room and pillar method", J. of Korean Tunn Undergr Sp Assoc, Vol. 15, No. 4, pp 443-453 (in Korean). https://doi.org/10.9711/KTAJ.2013.15.4.443
  16. Lunder, P.J., Pakalnis, R. (1997), "Determination of the strength of hard-rock mine pillars", Bull. Can. Inst. Min. Metall. Vol. 90, pp. 51-59.
  17. Mortazavi, A., Hassani, F.P., Shabani, M. (2009), "A numerical investigation of rock pillar failure mechanism in underground openings", Computers and Geotechnics, Vol. 36, Issue 5, pp. 691-697. https://doi.org/10.1016/j.compgeo.2008.11.004
  18. Murali Mohan, G., Sheorey, P.R., Kushwaha, A. (2001), "Numerical estimation of pillar strength in coal mines", International Journal of Rock Mechanics and Mining Sciences, Vol. 38, Issue 8, pp. 1185-1192. https://doi.org/10.1016/S1365-1609(01)00071-5
  19. Obert, L., Duvall, W.I. (1967), Rock mechanics and the design of structures in rock, Wiley, Londen.
  20. Omer, A., Akio, S., Noritoshi, Y., Kenrou, S., Toshikazu, K. (2000) "The characteristics of soft rocks and their effects on the long term stability of abandoned room and pillar lignite mines", Post Mining 2005, Nov. 16-17, Nancy, France.
  21. Potvin, Y., Hudyma, M.R., Miller, H.D.S. (1989), "Design guidelines for open stope support", Bull. Can. Min. Metall. Vol. 82, pp. 53-62.
  22. Sheorey, P.R., Loui, J.P., Singh, K.B., Singh, S.K. (2000), "Ground subsidence observations and a modified influence function method for complete subsidence prediction", Int. J. Rock Mech. Min. Sci. Vol. 37, pp. 801-818. https://doi.org/10.1016/S1365-1609(00)00023-X
  23. Shin, Y.-W., Kim, Y.-G. (2010) "Review of mechanical behaviors of pillar in large parallel tunnel", Journal of Korean Society for Rock Mechanics, Vol. 20, No. 3, pp. 131-144 (in Korean).
  24. Smith, S. (1990), Structural stability, support and excavation aspects of mine openings in stratified iron ore deposits, PhD Thesis, University of Nottingham.
  25. Swift, G.M., Reddish, D.J. (2002), "Stability problems associated with an abandoned ironstone mine", Bull. Eng. Geol. Environ 61, pp. 227-239. https://doi.org/10.1007/s10064-001-0147-9
  26. Wang, S.Y., Sloan, S.W., Huang, M.L., Tang, C.A. (2011) "Numerical study of failure mechanism of serial parallel rock pillars", J Rock Mechanics and Rock Engineering, Vol. 44, No. 2, pp 179-198. https://doi.org/10.1007/s00603-010-0116-3

Cited by

  1. Consideration on design procedure of room-and-pillar underground structure part I: parametric study vol.16, pp.5, 2014, https://doi.org/10.9711/KTAJ.2014.16.5.487
  2. Consideration on design procedure of room-and-pillar underground structure part II: selection of shape to design supports vol.16, pp.5, 2014, https://doi.org/10.9711/KTAJ.2014.16.5.497
  3. A study on drainage system of the room-and-pillar underground structure considering groundwater conditions vol.17, pp.6, 2015, https://doi.org/10.9711/KTAJ.2015.17.6.675
  4. Design of Unsupported Rock Pillars in a Room-and-Pillar Underground Structure by the Tributary Area Method and the Pillar Strength Estimation vol.24, pp.5, 2014, https://doi.org/10.7474/TUS.2014.24.5.335