Tunnel and Underground Space (터널과지하공간)

Korean Society for Rock Mechanics and Rock Engineering (한국암반공학회)
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Investigation of Frozen Rock Failure using Thermal Infrared Image

열적외선영상을 이용한 동결된 암석의 파괴특성 연구

  • 박지환 (서울대학교 공과대학 에너지시스템공학부) ;
  • 박형동 (서울대학교 공과대학 에너지시스템공학부)
  • Received : 2015.02.13
  • Accepted : 2015.03.10
  • Published : 2015.04.30
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Abstract

Mechanical energy is accumulated in the object when stress is exerted on rock specimens, and the failure is occurred when the stress is larger than critical stress. The accumulated energy is emitted as various forms including physical deformation, light, heat and sound. Uniaxial compression strength test and point load strength test were carried out in low temperature environment, and thermal variation of rock specimens were observed and analyzed quantitatively using thermal infrared camera images. Temperature of failure plane was increased just before the failure because of concentration of stress, and was rapidly increased at the moment of the failure because of the emission of thermal energy. The variations of temperature were larger in diorite and basalt specimens which were strong and fresh than in tuff specimens which were weak and weathered. This study can be applied to prevent disasters in rock slope, tunnel and mine in cold regions and to analyze satellite image for predicting earthquake in cold regions.

암석시료에 응력이 가해질 경우 역학적 에너지가 대상 물체에 누적되고, 대상 암석에 한계응력 이상이 가해질 경우 시료의 파괴가 발생한다. 이 때 시료 내부에 저장되어 있던 역학적 에너지는 물리적 변형뿐만 아니라 빛, 열, 소리 등 다양한 형태의 에너지로 발산된다. 본 연구에서는 $-10^{\circ}C$ 저온 환경에서 섬록암, 현무암, 응회암을 대상으로 일축압축강도 시험과 점하중강도 시험을 수행하고, 이때 발생하는 온도 변화를 열적외선카메라를 이용해 측정하고 정량적으로 분석하였다. 파괴 직전 파괴면에 응력이 집중되어 온도가 상승하였고, 파괴 순간 축적된 에너지가 열에너지의 형태로 방출되며 파괴면의 온도가 급격히 상승하는 것이 감지되었다. 강도가 높고 신선한 섬록암과 현무암 시료의 온도 상승폭이 상대적으로 강도가 낮고 풍화된 암석인 응회암 시료의 온도 상승폭에 비해 더 크게 나타났다. 본 연구결과는 저온지역에 위치한 암반사면, 터널, 광산 내부의 응력 집중지점을 감지해 향후 발생 가능한 재해를 예방하는데 적용될 수 있으며, 지진예측을 위한 위성영상 분석에도 적용될 것으로 기대된다.

Keywords

References

  1. Barker, G.A., 1934, Apparatus for detecting forest fires, US Patent No. 1,959,702.
  2. Brady, B.T. and G.A. Rowell, 1986, Laboratory investigation of the electrodynamics of rock fracture, Nature, 321, 488-482. https://doi.org/10.1038/321488a0
  3. Diakides. N.A. and J.D. Bronzino, 2008, Medical infrared imaging, CRC Press, 448p.
  4. Geng, N., C. Cui and M. Deng, 1993, The remote sensing observation in experiments of rock failure and the beginning of remote sensing rock mechanics, Acta Seismol. Sin., 6.4, 971-980. https://doi.org/10.1007/BF02651832
  5. Hardy, H.R., 1972, Application of acoustic emission techniques to rock mechanics research, ASTM STP 505, 41-83.
  6. Hyun, C.U., J. Park and H.D. Park, 2010, Investigation of rock failure under uniaxial loading using thermal infrared image, J. Kor. Soc. Geosystem Eng., 47.4, 505-514.
  7. Kim, H, J.I. Lee, M.Y. Choe, M. Cho, X. Zheng, H. Sang and J.Qiu, 2000, Geochronologic evidence for early crataceous volcanic activity on Barton Peninsula, King George Island, Antarctic, Polar Res., 19, 252-260.
  8. KSRM, 2005, Standard test method of rock, CIR, Seoul, Korea, 123p.
  9. Langley, S.P., 1881, The bolometer, The Society, New York, 7p.
  10. Liu, S., L. Wu and Y. Wu, 2006, Infrared radiation of rock at failure, Int. J. Rock Mech. Min. Sci., 43, 972-979. https://doi.org/10.1016/j.ijrmms.2005.12.009
  11. Martelli, G. and P. Cerroni, 1985, On the theory of radio frequency emission from macroscopic hypervelocity impacts and rock fracturing, Phys. Earth Planet. In., 40.4, 316-319. https://doi.org/10.1016/0031-9201(85)90041-X
  12. Massey, L.G., 2007, IR keeps West Virginia coal miners safe, Inframation 2007 Proc., Vol 8, 327-334.
  13. Parker, R.D., 1914, Thermic balance or radiometer, US Patent, No. 1,099,199.
  14. Shi, W., Y. Wu and L. Wu, 2007, Quantitative analysis of the projectile impact on rock using infrared thermography, Int. J. Impact Eng., 34, 990-1002. https://doi.org/10.1016/j.ijimpeng.2006.03.002
  15. Tihanyi, K., 1929, Automatic sighting and directing devices for torpedoes, guns and other apparatus, UK Patent No. 352,035.
  16. Vollmer, M. and K.P. Mollmann, 2011, Infrared Thermal Imaging: Fundamentals, Research and Applications, John Wiley & Sons, 612p.
  17. Wu, L. and J. Wang, 1998, Infrared radiation features of coal and rocks under loading, Int. J. Rock Mech. Min. Sci., 35.7, 969-976. https://doi.org/10.1016/S0148-9062(98)00007-2
  18. Wu, L. and S. Liu, 2009, Remote sensing rock mechanics and earthquake thermal infrared anomalies, Advances in Geoscience and Remote Sensing, Gary Jedlovec(Ed.), Intech, Rijeka, Croatia, pp. 709-742.
  19. Wu, L., C. Cui, N. Geng and J. Wang, 2000, Remote sensing rock mechanics (RSRM) and associated experimental studies, Int. J. Rock Mech. Min. Sci., 37, 879-888. https://doi.org/10.1016/S1365-1609(99)00066-0
  20. Wu, L., S. Liu, Y. Wu and C. Wang, 2006, Precursors for raock fracturing and failure-Part I: IRR image abnormalities, Int. J. Rock Mech. Min. Sci., 43, 473-482. https://doi.org/10.1016/j.ijrmms.2005.09.002
  21. Wu, L., S. Liu, Y. Wu and H. Wu, 2002, Changes in infrared radiation with rock deformation, Int. J. Rock Mech. Min. Sci., 39, 825-831. https://doi.org/10.1016/S1365-1609(02)00049-7
  22. Wu, L., Y. Wu, S. Liu, G. Li and Y. Li, 2004, Infrared radiation of rock impacted at low velocity, Int. J. Rock Mech. Min. Sci., 41, 321-327. https://doi.org/10.1016/S1365-1609(03)00099-6
  23. Yamada, I., M. Masuda, and H. Mizutani, 1989, Electromagnetic and acoustic emission associated with rock fracture, Phys. Earth Planet. In., 57.1-2, 157-168. https://doi.org/10.1016/0031-9201(89)90225-2