All Issue

2016 Vol.18, Issue 5 Preview Page
Numerical modeling of brittle failure of the overstressed rock mass around deep tunnel

심부 터널 주변 과응력 암반의 취성파괴 수치모델링

Kun-Chai Lee1*
,
Hyun-Koo Moon2
이 근채1*
,
문 현구2
1Hanyang University, Department of Natural Resources and Environmental Engineering, Ph. D Student
2Hanyang University, Department of Natural Resources and Environmental Engineering, Professor
1정회원, 한양대학교 자원환경공학과 박사과정
2비회원, 한양대학교 자원환경공학과 교수
*교신저자. *Corresponding Author. 
30 September 2016. pp. 469-485
PDF XML Citation
Abstract

The failure of rock mass around deep tunnel, different from shallow tunnel largely affected by discontinuities, is dominated by magnitudes and directions of stresses, and the failures dominated by stresses can be divided into ductile and brittle features according to the conditions of stresses and the characteristics of rock mass. It is important to know the range and the depth of the V-shaped notch type failure resulted from the brittle failure, such as spalling, slabbing and rock burst, because they are the main factors for the design of excavation and support of deep tunnels. The main features of brittle failure are that it consists of cohesion loss and friction mobilization according to the stress condition, and is progressive. In this paper, a three-dimensional numerical model has been developed in order to simulate the brittle behavior of rock mass around deep tunnel by introducing the bi-linear failure envelope cut off, elastic-elastoplastic coupling and gradual spread of elastoplastic regions. By performing a series of numerical analyses, it is shown that the depths of failure estimated by this model coincide with an empirical relation from a case study.

Keywords
Deep tunnel
Great depth
Overstress
Brittle failure
Depth of failure
Spalling

심부 터널 주변 암반의 파괴는 불연속면의 영향을 크게 받는 천부 터널 주변과 다르게 응력의 크기와 방향이 지배한다. 응력 지배 파괴의 양상은 응력 조건, 암석의 특성에 따라 연성과 취성으로 구분할 수 있으며 파석, 판상 파괴, 암석 파열 현상의 결과로 나타나는 V-형 홈 형태 취성 파괴 영역의 범위와 깊이는 심부 터널의 굴착과 보강 설계의 주요 인자이므로 이를 파악하는 것은 중요하다. 취성 파괴의 특성은 응력 조건에 따라 점착력 상실과 마찰력 전이로 구성된다는 점과 진행성 파괴라는 점이다. 본 연구는 이중 선형 절단 파괴 포락선과 탄성-탄소성 연계 해석과 점진적 탄소성 영역 확대라는 해석 절차와 방법을 도입하여 터널 주변 취성 암반의 파괴를 합리적으로 모사할 수 있는 3차원 수치 모델을 구현하였다. 이 수치 모델이 예상한 취성 파괴 영역의 깊이는 기존 사례 연구를 통한 경험식의 결과와 부합되었다.

키워드
심부 터널
대심도
과응력
취성 파괴
파괴 깊이
파석
References
1
Amadei, B., Stephansson, O. (1997). Rock stress and its measurement. Chapman & Hall.
2
Aydan, Ö., Akagi, T., Kawamoto, T. (1996). The Squeezing Potential of Rock Around Tunnels: Theory and Prediction with Examples from Japan. Rock Mech. Rock Eng., Vol. 29, No. 3, pp. 125-143.
3
Brown, E. T., editor (1981). Rock Characterization Test and Monitoring: ISRM Suggested Methods. Pergamon Press.
4
Brown, E. T., Hoek, E. (1978). Trends in Relationships between Measured In-Situ Stresses and Depth., Int. J. Rock Mech. Min. Sci. & Geomech. Abstr., Vol. 15, No. 4, pp. 211-215.
5
Cai, M., Kaiser, P., Tasaka, Y., Maejima, T., Morioka, H., Minami, M. (2004). Generalized crack initiation and crack damage stress thresholds of brittle rock masses near underground excavations. Int. J. Rock Mech. Min. Sci., Vol. 41, No. 5, pp. 833-847.
6
Cai, M., Kaiser, P.K. (2014). In-situ Rock Spalling Strength near Excavation Boundaries. Rock Mech. Rock Eng., Vol. 47, No. 2, pp. 659-675.
7
Cundall, P., Carranza-Torres, C., Hart, R. (2003). A new constitutive model based on the Hoek-Brown criterion. In Brummer, R. et al., editor, FLAC and Numerical Modeling in Geomechanics – 2003 (Proceedings of the 3rd International FLAC Symposium, Sudbury, Ontario, Canada, October 2003), pp. 17-26, Lisse. Balkema.
8
Diederichs, M.S. (2003). Manuel Rocha Medal Recipient Rock Fracture and Collapse Under Low Confinement Conditions. Rock Mech. Rock Eng., Vol. 36, No. 5, pp. 339-381.
9
Hajiabdolmajid, V., Kaiser, P., Martin, C. (2002). Modelling brittle failure of rock. Int. J. Rock Mech. Min. Sci., Vol. 39, No. 6, pp. 731-741.
10
Hoek, E., Guevara, R. (2009). Overcoming Squeezing in the Yacambú-Quibor Tunnel, Venezuela. Rock Mech. Rock Eng., Vol. 42, No. 2, pp. 389-418.
11
Hoek, E., Kaiser, P.K., Bawden, W.F. (1995). Support of Underground Excavations in Hard Rock. A. A. Balkema, Rotterdam.
12
Hoek, E., Marinos, P.G. (2008). Tunnelling in over-stressed rock. In Vrkljan, I., editor, Rock Engineering in Difficult Ground Conditions - Soft Rocks and Karst, pages 49-60, London. Taylor and Francis Group.
13
Kaiser, P.K., Cai, M. (2012). Design of rock support system under rockburst condition. J. Rock Mech. Geotech. Eng., Vol. 4, No. 3, pp. 215-227.
14
Kaiser, P.K., Diederiches, M.S., Martin, C.D., Sharp, J., Steiner, W. (2000). Underground Works in Hard Rock Tunnelling and Mining. In ISRM International Symposium, Melbourn, Australia.
15
Martin, C.D. (1995). Brittle rock strength and failure: Laboratory and in situ. In Fujii, T., editor, Pro-ceedings of the 8th, ISRM Congress on Rock Mechanics, Tokyo. Vol. 3, pp. 1033-1040. A. A. Balkema.
16
Martin, C.D. (1997). Seventeenth canadian geotechnical colloquium: The effect of cohesion loss and stress path on brittle rock strength. Canadian Geotechnical Journal, Vol. 34, No. 5, pp. 698-725.
17
Martin, C.D., Chandler, N.A. (1994). The Progressive Fracture of Lac du Bonnet Granite. Int. J. Rock Mech. Min. Sci. & Geomech. Abstr., Vol. 31, No. 6, pp. 643-659.
18
Martin, C.D., Christiansson, R., Söderhäll, J. (2001). Rock stability considerations for siting and constructing a KBS-3 repository Based on experiences from Äspö HRL, AECL’s URL, tunneling and mining. Technical report, TR-01-38, Swedish Nuclear Fuel and Waste Management Company, Stockholm.
19
Martin, C.D., Kaiser, P.K., McCreath, D.R. (1999). Hoek-Brown parameters for predicting the depth of brittle failure around tunnels. Canadian Geotechnical Journal, Vol. 36, pp. 136-151.
20
McCutchen, W. (1982). Some Elements of a Theory for In-situ Stress. Int. J. Rock Mech. Min. Sci. & Geomech. Abstr., Vol. 19, No. 4, pp. 201-203.
21
Mezger, F., Anagnostou, G., Ziegler, H.J. (2013). The excavation-induced convergences in the Sedrun section of the Gotthard Base Tunnel. Tunnelling Underground Space Technol, Vol. 38, pp. 447-463.
22
Panet, M. (1996). Two Case Histories of Tunnels Through Squeezing Rocks. Rock Mech. Rock Eng., Vol. 29, No. 3, pp. 155-164.
23
Read, R., Chandler, N., Dzik, E. (1998). In situ strength criteria for tunnel design in highly-stressed rock masses. Int. J. Rock Mech. Min. Sci., Vol. 35, No. 3, pp. 261-278.
24
Roby, J., Willis, D., Carollo, B.S. (2008). Coping with difficult ground and 2000 m of cover in peru. In World Tunnel Congress 2008 - Underground Facilities for Better Environment and Safety, pp. 1003-1016.
25
Sheorey, P.R. (1994). A Theory for In Situ Stresses in Isotropic and Transversely Isotropic Rock. Int. J. Rock Mech. Min. Sci. & Geomech. Abstr., Vol. 31, No. 1, pp. 23-34.
26
Wang, J., Zeng, X., Zhou, J. (2012). Practices on rockburst prevention and control in headrace tunnels of Jinping II hydropower station. J. Rock Mech. Geotech. Eng., Vol. 4, No. 3, pp. 258-268.
Information
  • Publisher :Korean Tunneling and Underground Space Association
  • Publisher(Ko) :한국터널지하공간학회
  • Journal Title :Journal of Korean Tunnelling and Underground Space Association
  • Journal Title(Ko) :한국터널지하공간학회 논문집
  • Volume : 18
  • No :5
  • Pages :469-485
  • Received Date : 2016-09-08
  • Revised Date : 2016-09-23
  • Accepted Date : 2016-09-26
  • DOI :https://doi.org/10.9711/KTAJ.2016.18.5.469
Journal Informaiton Journal of Korean Tunnelling and Underground Space Association Journal of Korean Tunnelling and Underground Space Association
Online Submission & Review System
  • NRF
  • KOFST
  • KISTI Current Status
  • KISTI Cited-by
  • crosscheck
  • orcid
  • open access
  • ccl
Journal Informaiton Journal Informaiton - close