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Slope stability analysis and landslide hazard assessment in tunnel portal area

터널 갱구지역 사면안정성 및 산사태 위험도 평가

  • Jeong, Hae-Geun (K-water Institute, Korea Water Resources Corporation) ;
  • Seo, Yong-Seok (Department of Earth and Environmental Sciences, Chungbuk National University)
  • 정해근 (한국수자원공사 K-water 연구원) ;
  • 서용석 (충북대학교 지구환경과학과)
  • Received : 2013.05.14
  • Accepted : 2013.07.09
  • Published : 2013.07.31

Abstract

In this study, the slope stability analysis and the landslide hazard assessment in tunnel portal slope were carried out. First, we selected highly vulnerable areas to slope failure using the slope stability analysis and analyzed the slope failure scale. According to analyses results, high vulnerable area to slope failure is located at 485~495 m above sea level. The slope is stable in a dry condition, while it becomes unstable in rainfall condition. The analysis results of slope failure scale show that the depth of slope failure is maximum 2.1 m and the length of slope failure is 18.6 m toward the dip direction of slope. Second, we developed a 3-D simulation program to analyze characteristics of runout behavior of debris flow. The developed program was applied to highly vulnerable areas to slope failure. The result of 3-D simulation shows that debris flow moves toward the central part of the valley with the movement direction of landslide from the upper part to the lower part of the slope. 3-D simulation shows that debris flow moves down to the bottom of mountain slope with a speed of 7.74 m/s and may make damage to the tunnel portal directly after 10 seconds from slope failure.

Acknowledgement

Supported by : 한국연구재단

References

  1. Bae, S.H. (2007), "Cause analysis of 2006 concentrated heavy rain which occurred in Inje-Gun", The Korean Association of Regional Geographers, Vol. 13, No. 4, pp. 396-408.
  2. Chae, B.G., Kim, W.Y., Cho, Y.C., Kim, K.S., Lee, C.O., Choi, Y.S. (2004b), "Development of a logistic regression model for probabilistic prediction of debris flow", The Journal of Engineering Geology, Vol. 14, No. 2, pp. 211-222.
  3. Chae, B.G., Kim, W.Y., Na, J.H., Cho, Y.C., Kim, K.S., Lee, C.O. (2004a), "A prediction model of landslides in the teriary sedimentary rocks and volcanic rocks area", The Journal of Engineering Geology, Vol. 14, No. 4, pp. 443-450.
  4. Cho, Y.C., Chae, B.G., Kim, W.Y., Chang, T.W. (2007), "A modified logistic regression model for probabilistic prediction of debris flow at the granitic rock area and its application - landslide prediction map of gangreung area", The Korean Society of Economic and Environmental Geology, Vol. 40, No. 1, pp. 115-128.
  5. Hazen, A. (1911), "Discussion: dams on sand foundations", Transactions of the American Society of Civil Engineers, Vol.73, pp. 199.
  6. Institute of Chubu Nihon Kogyo (2007), Technical report for 3D landslide simulation.
  7. Iverson, J.B. (1998), "Molecules, morphology, and mud turtle phylogenetics (Family Kinosternidae)", Chelonian Conservation and Biology, Vol. 3, No. 1, pp. 113-117.
  8. Kim K.S., Song Y.S., Chae B.G., Cho Y.C., Lee Y.C. (2007), "Geometric characteristics of landslides on natural terrain according to the geological condition", The Journal of Engineering Geology, Vol. 17, No. 1, pp. 75-87.
  9. Kim, W.Y., Chae, B.G., Kim, K.S., Kee, W.S., Cho, Y.C., Choi, Y.S., Lee, S.R., Lee, B.J. (2000), "Study on landslide hazard prediction", MOE, KR-00-(T)-09.
  10. Korea Meteorological Administration (2008), Internet homepage (http://www.kma.go.kr).
  11. Lee, S.R., Kim, Y.J., Min, K.D. (2000), "Development of spatial landslide information system and application of spatial landslide information", The Journal of GIS Association of Korea, Vol. 8, No. 1, pp. 141-153.
  12. Oliver, M., Bell, F.G., Jemy, C.A. (1994), "The effects of rainfall on slope failure, with examples from the greater durban area", In: Proceedings Seventh Congress International Association Engineering Geology, Lisbon, A.A. Balkema, Rotterdam, Vol. 3, pp. 1629-1636.
  13. Seo, Y.S., Chae, B.G., Kim, W.Y., Song, Y.S. (2005), "Assessment of runout distance of debris using the artificial neural network", The Journal of Engineering Geology, Vol. 15, No. 2, pp. 145-154.
  14. Stevens, N.F., Manville, V., Heron, D.W., (2002), "The sensitivity of a volcanic flow model to digital elevation model accuracy: experiments with digitised map contours and interferometric SAR at ruapehu and taranaki volcanoes", New Zealand, Journal of Volcanology and Geothermal Research, Vol. 119, Issue 1-4, pp. 89-105.
  15. Stolz, A., Huggel, C. (2008), "Debris flows in the swiss national park: the influence of different flow models and varying DEM grid size on modeling results, Landslides", Vol. 5, Issue 3, pp. 311-319. https://doi.org/10.1007/s10346-008-0125-4
  16. Zhang, C., Iwahori, Y. (2003), "Numerical prediction of mass movement due to slope collapse", The Japan Landslide Society, pp. 555-558.