Journal of the Korean GEO-environmental Society (한국지반환경공학회 논문집)

Korean Geo-Environmental Society (한국지반환경공학회)
권호 표지
DOI QR코드

DOI QR Code

The Study for Enhancing Resilience to Debris Flow at the Vulnerable Areas

토석류 재해발생 시 레질리언스 강화를 위한 연구

  • Kim, Sungduk (Dept of Civil & Environment Engineering, Cheongju University) ;
  • Lee, Hojin (School of Civil Engineering, Chungbuk National University) ;
  • Chang, Hyungjoon (School of Civil Engineering, Chungbuk National University) ;
  • Dho, Hyonseung (Dept of Civil & Environment Engineering, Cheongju University)
  • Received : 2021.05.21
  • Accepted : 2021.07.01
  • Published : 2021.08.01
Download PDF
⟨ Previous Next ⟩

Abstract

Climate change caused by global warming increases the frequency of occurrence of super typhoons and causes various types of sediment disasters such as debris flows in the mountainous area. This study is to evaluate the behavior of debris flow according to the multiplier value of the precipitation characteristics and the quantity of debris flow according to the typhoon category. For the analysis of the debris flow, the finite difference method for time elapse was applied. The larger the typhoon category, the higher the peak value of the flow discharge of debris flow and the faster the arrival time. When the precipitation characteristic multiplier is large, the fluctuation amplitude is high and the bandwidth is wide. When the slope angle was steeper, water discharge increased by 2~2.5 times or more, and the fluctuation of the flow discharge of debris flow increased. All of the velocities of debris flow were included to the class of "Very rapid", and the distribution of the erosion or sedimentation velocity of debris flows showed that the magnitude of erosion increased from the beginning, large-scale erosion occurred, and flowed downstream. The results of this study will provide information for predicting debris flow disasters, structural countermeasures and establishing countermeasures for reinforcing resilience in vulnerable areas.

지구 온난화로 인한 기후변화는 슈퍼 태풍의 발생빈도를 높이고 산지에서 토석류와 같은 다양한 형태의 토사재해를 야기한다. 본 연구는 태풍 등급에 따른 토석류 발생량 및 강우특성의 가중치에 따른 토석류 거동을 평가한 것이다. 토석류 해석은 시간 변화에 대한 유한차분법을 적용하였다. 태풍의 범주가 클수록 토석류 유량의 peak 값이 크고 도달시간도 빠르게 나타났다. 강수특성 가중치가 큰 경우 fluctuation 진폭이 크고 밴드폭이 넓게 나타났다. 경사면의 각도가 큰 경우 2~2.5배 이상 상승하였고, 토석류 유량의 fluctuation의 변동성이 확대되었다. 토석류의 유속은 모두가 급속도(Very rapid)에 해당하는 클래스에 속하였고, 토석류의 침식 또는 퇴적 속도의 분포는 초기부터 침식의 크기가 커졌으며 대규모의 침식이 발생하고 하류로 유하하는 것을 나타냈다. 이상에서 본 연구의 결과는 토석류 재해의 예측 및 구조물적 대책, 재해 취약지역에서 레질리언스 강화를 위한 대책을 세우는 데 중요한 정보를 제공할 것이다.

Keywords

References

  1. DeGraff, J. (1994), The Geomorphology of Some Debris Flows in the Southern Sierra Nevada, California: Geomorphology, No. 10, pp. 231~252.
  2. Denlinger, R. P. and Iverson, R. M. (2001), Flow of variably fluidized granular masses across three-dimensional terrain, numerical predictions and experimental tests, Journal of Geophysical Research, Vol. 106, No. B1, pp. 553~566. https://doi.org/10.1029/2000JB900330
  3. Department of Environmental Protection (2015) in New Jersey, Disaster Debris Management Planning Tool Kit For New Jersey Municipalities.
  4. Egashira, S. Miyamoto, K. and Itoh, T. (1997), Constitutive equation of debris flow and their applicability, 1st International Conferenceon Debris-Flow Hazards Mitigation, ASCE, pp. 340~349.
  5. Ghilardi, P., Natale, L. and Savi, F. (2001), Modeling debris flow propagation and deposition, Physics and Chemistry of the Earth, Vol. 26, No. 9, pp. 651~656.
  6. Gori, P. L. and Burton, W. C. (1996), Debris Flow Hazards in the Blue Ridge of Virginia: U.S. Geological Survey Fact Sheet, pp. 159~96.
  7. Kim, S. D. and Lee, H. J. (2019), Numerical simulation of the impact force of debris flow according to the characteristics of the liquefied layer of sediment, Journal of Disaster Management, Vol. 19, No. 2 , pp. 113~119 (In Korean).
  8. Kim, S. D., Oh, S. W. and Lee, H. J. (2013), The study of relationship between berm width and debris flow at the slope, Journal of the Korean Geo-Environmental Society, Vol. 14, No. 11, pp. 5~12 (In Korean). https://doi.org/10.14481/jkges.2013.14.12.005
  9. Lee, H. J., Kim, S. D., Lee, M. S. and Jun, K. W. (2015), The modeling of debris flow disaster according to the location of berm, Crisisonomy, No. 11, Vol. 9, pp. 105~118 (In Korean).
  10. Luzi, L., Pergalani, F. and Terlien, M. T. J. (2000), Slope vulnerability to earthquakes at subregional scale, using probabilistic techniques and geographic information systems, Engineering Geology, Vol. 58, Issues 3~4, pp. 313~336. https://doi.org/10.1016/S0013-7952(00)00041-7
  11. Nakagawa, H., Takahashi, T., Satofuka, Y. and Kawaike, K. (2003), Numerical simulation of sediment disasters caused by heavy rainfall in Camuri Grande basin, Proceedings of the Third Conference on Debris-Flow Hazards Mitigation: Mechanics, Prediction, and Assessment, Switzerland, Rotterdam, Venezuela 1999, pp. 671~682.
  12. O'Brien, J. S., Julien, P. Y. and Fullerton, W. T. (1993), Twodimensional water flood and mudflow simulation, Journal of Hydraulic Engineering, Vol. 119, No. 2, pp. 244~266. https://doi.org/10.1061/(ASCE)0733-9429(1993)119:2(244)
  13. Park, J. H., Seo, J. I. and Lee, C. W. (2019), Analysis of GIS for characteristics on the slow-moving landslide: with a special reference on slope and grade of landslide, Journal of Korean Society of Forest Science, Vol. 108, No. 3, pp. 311~321 (In Korean).
  14. Savage, S. B. and Hutter, K. (1991), The dynamics of avalanches of granular materials from initiation to runout. Part I: Analysis, Acta Mechanica, Vol. 86, pp. 201~223. https://doi.org/10.1007/BF01175958
  15. Takahashi, T., Nakagawa, H., Harada, T. and Yamashiki, Y. (1992), Routing debris flows with particle segregation, Journal of Hydraulic Engineering, Vol. 118, No. 11, pp. 1490~1507. https://doi.org/10.1061/(ASCE)0733-9429(1992)118:11(1490)
  16. Takahashi, T. and Tsujimoto, H. (1984), Mechanics of granular flow in inclined chute, Journal of Hydraul Coast. Environment Engineering, JSCE, Vol. 565, No. 2-39, pp. 57~71 (In Japanese).
  17. Wang, N. S., Yi, R. H. and Liu, D. (2008), A solution method to the problem proposed by wang in voting systems, Journal of Computational and Applied Mathematics, Vol. 221, pp. 106~113. https://doi.org/10.1016/j.cam.2007.10.006
  18. WP/WLI. (1995), A suggested method for describing the rate of movement of a landslide, Bulletin of the International Association of Engineering Geology, No. 52, pp. 75~78.