지질공학 (The Journal of Engineering Geology)

  • 제15권3호
  • /
  • Pages.269-280
  • /
  • 2005
  • /
  • 1226-5268(pISSN)
  • /
  • 2287-7169(eISSN)
대한지질공학회 (The Korean Society of Engineering Geology)
권호 표지

수정 분할자법을 이용한 절리 거칠기 계수(JRC)의 정량화

Estimation of Joint Roughness Coefficient(JRC) using Modified Divider Method

  • 장현식 (강원대학교 지구물리학과) ;
  • 장보안 (강원대학교 지구물리학과) ;
  • 김열 (한국도로공사 도로교통기술원)
  • Jang Hyun-Shic (Dept. of Geophysics, Kangwon National University) ;
  • Jang Bo-An (Dept. of Geophysics, Kangwon National University) ;
  • Kim Yul (Highway & Transportation Technology Institute, Korea Highway Corporation)
  • 발행 : 2005.09.01
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

Barton and Choubey(1977)가 제안한 표준 거 칠기 단면을 0.1mm 간격으로 수치화한 후 수정 분할자법을 이용하여 분할자 길이에 따른 단면의 길이를 측정하였다. 분할자 길이에 따른 단면의 길이를 log-log 그래프에 도시 한 후 직선회기 분석 을 통하여 표준 거 칠기 단면의 프랙탈 차원과 절편을 구하고, JRC와의 관계를 분석하였다. 정확한 프랙탈 차원을 계산할 수 있는 분할자의 길이 범위인 교차거리는 $0.3\sim2.4mm$ 내외이며, JRC는 프랙탈 차원보다는 절편과 더 높은 상관도를 보였다. 그러나 프랙탈 차원과 절편을 곱하였을 때 가장 좋은 상관도를 보였으며, 위의 결과를 이용하여 프랙탈 차원과 절편을 이 용한 새로운 IRC 추정식 을 도출하였다. 23개의 자연 암석 절리의 단면을 수치화하여 $Z_2$ 파라미터를 이용한 Tse and Cruden (1979) 식과 새로운 JRC 관계식으로 각 단면의 JRC를 계산하고 이를 비교하였다. 비교 결과 두 관계식으로 추정된 JRC는 매우 유사하여, 본 연구에 서 도출된 새로운 관계식은 IRC를 추정하는데 매우 유용할 것으로 판단된다.

We assigned points on surface of standard roughness profile by 0.1mm along the length and measured coordinates of points. Then, the lengths of profile were measured with different scales using modified divider method. The fractal dimensions and intercepts of slopes were determined by plotting the length vs scale in log-log scale. The fractal dimensions as well as intercepts of slopes show well correlation with joint roughness coefficients(JRC). However, multiplication of the kactal dimension by intercept show better correlation with IRC and we derived a new equation to estimate JRC from fractal dimension and intercept. The crossover length in which we can determine the correct fractal dimension was between 0.3-3.2mm. We measured joint roughness of 26 natural joints and calculated JRC using the equation suggested by Tse and Cruden(1979) and new equation derived by us. IRC values calculated by both equations are almost the same, indicating new equation is effective in measuring IRC.

키워드

참고문헌

  1. (주)사이버출판사, 2001, 퍼펙트 한글코렐드로우 8, pp. 114-181
  2. 이상돈, 1996, 절리형상의 정량적 측정을 통한 각종 거칠기 파라미터의 비교분석 및 전단거동 해석, 서울대학교 박사학위논문, pp. 1-90
  3. Barton, N. and Choubey, V., 1977, The shear strength of rock joints in theory and practice, Rock Mechanics.10:1-54 https://doi.org/10.1007/BF01261801
  4. Berry, M. V. and Lewis, Z. V. 1980. On the Weierstrass-Mandelbroit fractal function. Proc. of the Royal society of London, Ser. A.370: 459-484
  5. Brown, S. R., 1987. A note on the description of surface rouglmess using fractal dimension, Geophysical Research Letters. 14(11): 1095-1098 https://doi.org/10.1029/GL014i011p01095
  6. Feder, J. 1988. Fractals, Plenum Press, New York, 283
  7. Krahn,J. and Morgenstern, N. R., 1979. The ultimate frictional resistance of rock discontinuities. Tnt. J. Rock Mech, Min, Sci. & Geomech. Abstr. 16: 127-133
  8. Kulatilake, P. H S. W., Shou, G. Huang, T. H. and Morgan, R. M., 1995. New peak shear strength criteria for anisotropic rock joints. Int. J. Rock Mech, Min, Sci. & Geomech. Abstr. 32(7): 673-697 https://doi.org/10.1016/0148-9062(95)00022-9
  9. Kulatilake, P. H. S. W., Um, J., and Pan, G., 1997. Requirements for accurate estimation of fractal parameters for self-affine roughness profiles using the line scaling method. Rock Mech, Rock Engng. Springer-Verlag. 30(4): 181-206 https://doi.org/10.1007/BF01045716
  10. Lee, Y. H., Carr, J. R, Barr, D. J., and Hass, C. J., 1990. The fractal dimension as a measure of roughness of rock discontinuity profile. Int. J. Rock Mech, Min, Sci. & Geomech. Abstr. 27(6): 453-464 https://doi.org/10.1016/0148-9062(90)90998-H
  11. Malinverno, A. 1990. A simple method to estimate the fractal dimension of a self affine series. J. Geophys. Res. Lett. 7: 1953-1956
  12. MIler, 5. M., Mcwilliams, P. C. and Kerkering J. C., 1990, Ambiguities in estimating fractal dimensions of rock fractal surfaces, proceedings, Rock Mechanics Contribution and Challenges, eds: Hustruid & Johnson pp. 147-478
  13. Myers, N. O., 1962. Characteristics of surface roughness, Wear. 5: 182-189 https://doi.org/10.1016/0043-1648(62)90002-9
  14. Orey, S. 1970. Gaussian Sample Fuction and Housdorff Dimension of Level Crossing. x. Wahrsheninkeits theorie verw. Gebierte 15: 249-256
  15. Seidel, J. P., Haberfield, C. M, 1995, Towards and Under-standing of Joint Rouglmess, Rock Mechanics and Rock Engineering, springer-Verlag, 28.2, pp. 69-92 https://doi.org/10.1007/BF01020062
  16. Tse, R. and Cruden, D. M., 1979. Estimating joint roughness coefficients, Int. J. Rock Mech, Min, Sci. & Geomech. Abstr. 16: 303-307 https://doi.org/10.1016/0148-9062(79)90241-9
  17. Turk, N., Gerd, M. J, Dearman, W. R. and Amin, F. F., 1987, Characterization of rock joint surfaces by fractal dimension, proc. 28th U.S. Symp. on Rock Mechanics, Tucson, Balkema, Rotterdam, 1223-1236
  18. Wakabayashi, N. and Fukushige, I., 1995. Experimental study on the Relation between fractal dimension and shear strength. Fractured and jointed Rock Masses, Myer, Cook, Goodman & Tsang (eds). Balkema. Rotterdam, ISBN 9054105917: 125-131
  19. Wu, T. H. and Ali, E. M. 1978. Statistical Representation of the joint roughness, Int. J. Rock. Mech. Min. Sci. & Geomech. Abstr. 15: 259-262 https://doi.org/10.1016/0148-9062(78)90958-0