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Research Article

Characteristic Analysis of Shear Strength of Rock Slope Discontinuity in Yangsan Fault System

양산단층대 암반비탈면에 분포하는 불연속면의 전단강도 특성분석

Hak-Ju Lee1
,
Chang-Ho Kim2
,
Woong-Ki Hwang3
,
Tae-Hyung Kim4*
이 학주1
,
김 창호2
,
황 웅기3
,
김 태형4*
1Nonmember, Graduate Student, Dept. of Civil and Environ. Eng., Korea Maritime and Ocean Univ., 727 Taejoung-ro, Yeongdo-gu, Busan 49112, Republic of Korea
2Nonmember, Deputy General Manager, Korea Expressway Corp., 77 Hyeoksin 8-ro, Gimchon-si, Gyeongsanbuk-do 39660, Republic of Korea
3Member, Manager, Geotechnical Research & Development Co., Ltd., 60 Centum jungang-ro, Haeundae-gu, Busan 48059, Republic of Korea
4Member, Professor, Dept. of Civil Eng., Korea Maritime and Ocean Univ., 727 Taejoung-ro, Yeongdo-gu, Busan 49112, Republic of Korea
* Corresponding Author
30 September 2019. pp. 11-22
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Abstract

본 연구는 양산단층대를 통과하는 고속도로 건설공사 중 암반비탈면의 파괴가 유난히 많이 발생된 원인을 규명하기 위하여 수행하였다. 이를 위해 128개소의 양산단층대 파괴 암반비탈면 대하여 불연속면 유형(절리, 층리, 단층)에 따라 face mapping과 역해석을 통해 전단강도(점착력, 내부마찰각)를 재 산정하였다. 재 산정된 점착력과 내부마찰각에 대해 분석을 하였으며 기존 문헌 및 설계 값과도 비교를 하였다. 전체적으로 본 연구에서 재 산정된 점착력과 내부마찰각이 기존 문헌 및 설계에 적용된 값보다 작은 것으로 나타났다. 이와 같은 이유로 시공 중 많은 암반비탈면에서 파괴가 발생된 것으로 보인다. 이것은 연구 대상 지역의 쇄설성퇴적암이 가지고 있는 특성과 발달된 불연속면이 큰 역할을 한 것으로 판단된다. 특히 층리 불연속면인 경우 기존 값과 비교 시 가장 큰 차이를 보이는 것으로 나타났다. 불연속면에 점토충진물이 존재하는 경우 불연속면의 유형에 따라 전단강도가 서로 다른 경향을 보이는 반면, 파쇄물이 존재하는 경우에는 전단강도 값은 불연속면의 유형에 상관없는 것으로 나타났다.

This study was conducted to identify the causes of the unusually high number of rock slope failures during an expressway construction in Yangsan fault system. The shear strength (cohesion and internal friction angle) of 128 slopes of discontinuities including bedding, joint, and fault planes were re-evaluated through the examination of face mapping and back analysis. The re-evaluated values were analyzed and then compared with the existing data and values used in the design. As a result, the re-evaluated cohesion and friction angles were very low compared to the existing data and the values applied in the design. This incongruity was pointed as the primary reason for the rock slopes failures during the construction. This may be related to the inherent features of clastic sedimentary rocks in the study area, and the discontinuities in the sedimentary rocks in this region played a significant role. Especially, bedding discontinuity showed a big difference compared to the existing data. The shear strength depended on the type of discontinuity in case of clay filled in discontinuity. However, shear strength was independent on the type of discontinuity in case of shattered materials filled in discontinuity.

Keywords
Shear strength
Clastic sedimentary rock
Yangsan fault
Bedding
Joint

References
1
Aydan, Ö., Shimizu, Y. and Ichikawa, Y. (1989), “The Effective Filure Modes and Stability of Slopes in Rock Mass with Two Discontinuity Sets”, Rock Mechanics and Rock Engineering, Vol.22, No.3, pp.163-188.
10.1007/BF01470985
2
Barton, N. R. (1976), The Shear Strength of Rock and Rock joints. Int. J. Rock Mech. Min. Sci. Geomech. Abstr., 13: pp.255-279.
10.1016/0148-9062(76)90003-6
3
Barton, N. R. (1973), Review of a New Shear Strength Criterion for Rock Joints, Eng. Geol., Vol.7, pp.287-332.
10.1016/0013-7952(73)90013-6
4
Barton, N. R. (1974), A Review of the Shear Strength of Filled Discontinuities in Rock, Norwegian Geotech. Inst. Publ. No.105.
5
Barton, N. R. and Choubey, V. (1977), The Shear Strength of Rock Joints in Theory and Practice, Rock Mech. Vol.10, No.1-2, pp.1-54.
10.1007/BF01261801
6
Choi, E. K., Kim, S. W., Kim, I. S. and Lee, K. H. (2012), A Study on the Chemical Index of Alteration of Igneous Rocks, Journal of the Korean Geotechnical Society, 28(3), pp.41-54 (in Korean with English abstract).
10.7843/kgs.2012.28.5.41
7
Haque, A. and Kodikara, J. (2012), A Simplified Analytical Model for Predicting the Shear Behavior of Regular Triangular Rock/Concrete Joints under Constant Normal Stiffness, Geotechnique, 62(2), pp.171-176.
10.1680/geot.8.T.018
8
Hoek, E. (1990), Estimating Mohr-Coulomb Friction and Cohesion Values from the Hoek-Brown Failure Criterion, International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts, Vol.27, No.3, pp.227-229.
10.1016/0148-9062(90)94333-O
9
Hoek, E. and Bray, J. D. (1974), Rock Slope Engineering, CRC Press, p.368.
10
Hoek, E. and Brown, E. T. (1997), Practical Estimates of Rock Mass Strength, International Journal of Rock Mechanics and Mining Sciences, Vol.34, No.8, pp.1165-1186.
10.1016/S1365-1609(97)80069-X
11
Jaeger, J. C. (1971), Friction of Rocks and the Stability of Rock Slopes, Rankine Lecture. Geotechnique, 21, pp.97-134.
10.1680/geot.1971.21.2.97
12
Kim, C.-H., Kim, B.-Y., Park, T.-W. and Kim, T.-H. (2018), Estimation of Shear Strength of Discontinuous(bedding) Cut Sedimentary Rock Slope by Using Back Analysis, J. Korean Geosynthetics Society, Vol.17, No.1, pp.139-152.
13
Kim, K. S., You, B. O. and Lee, S. D. (2002), Failure Characteristics of Cut Slopes of Shale in Kyoungsang Basin, Proceedings of the seminar and field workshop for mudstone and shale, organized by the Korean Geotechnical Socity for Rock Mechanics Commission, pp.103-114.
14
Kim, S.-W., Choi, E.-K., Kim, J.-W., Kim, T.-H. and Lee, K.-H. (2017), Chemical Weathering Index of Clastic Sedimentary Rocks in Korea, The Journal of Engineering Geology, Vol. 27, No.1, pp.67-79.
15
Korea Expressway Corporation (2001), Design Reports the Busan-Ulsan Expressway.
16
Korea Expressway Corporation (2008), Reports of Slope Stability Analysis on the Busan-Ulsan Expressway Construction Site.
17
Lee, S. H. and Kim, S. J. (2004), “Weathering Characteristics of Sedimentary Rocks Affected by Periodical Submerging”, Journal of Mineralogical Society of Korea, Vol.17, No.1, pp.23-35.
10.9727/jmsk.2018.31.1.23
18
Park. H. D. (2002), “Engineering Geological Properties of Mudstone and Shale”, Proc. of the seminar and field workshop for mudstone and shale, organized by the Korean Geotechnical Socity for Rock Mechanics Commission, pp.18-30.
19
Patton, F. D. (1966), Multiple Modes of Shear Failure in Rock, Proc. of the 1st Internation-al Cong. on Rock Mech., Lisbon, 1, pp.509-515.
20
Prist S. D. (1992), Discontinuity Analysis Rock Engineering, Chapman & Hall, London, Vol.228, No.13, pp.39-49.
21
Son, M., Kim, I.-S., Lee, D. H., Lee J.-D., Kim, J. S. and Paik, I. S. (2000), “Geological Characteristics in the Eastern Part of the Ulsan Fault Area, Korea : Structural Geology and Anisotropy of Magnetic Susceptibility(AMS) in the Tertiary Miocene Waup Basin”, Journal of the Geological Society of Korea, Vol.36, No.3, pp.195-216.
22
You, B. O. (2002), Assumption of Shear Strength on Failed Discontinuities Due to Back Analysis, Proc. of fall conference of the Korean Geotechnical Society, pp.213-227.
Information
  • Publisher :Korean Geosythetics Society
  • Publisher(Ko) :한국지반신소재학회
  • Journal Title :Journal of the Korean Geosynthetics Society
  • Journal Title(Ko) :한국지반신소재학회 논문집
  • Volume : 18
  • No :3
  • Pages :11-22
  • Received Date : 2019-05-15
  • Revised Date : 2019-07-10
  • Accepted Date : 2019-08-15
  • DOI :https://doi.org/10.12814/jkgss.2019.18.3.011
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