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The Study for Analysis of Impact Force of Debris Flow According to the Location of Check Dam

사방댐 위치변화에 따른 토석류의 충격력 해석에 관한 연구

  • Kim, Sung-Duk (School of Cilvil Engineering, Chungbuk National University) ;
  • Lee, Ho-Jin (School of Cilvil Engineering, Chungbuk National University) ;
  • Chang, Hyung-Joon (School of Cilvil Engineering, Chungbuk National University)
  • Received : 2018.11.09
  • Accepted : 2019.01.04
  • Published : 2019.01.31
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Abstract

Debris flows occur in mountainous areas due to heavy rains resulting from climate change and result in disasters in the downstream area. The purpose of this study is to estimate the impact force of a debris flow when a check dam according is installed in various locations in the channel of a highly mountainous area. A Finite Differential Element Method (FDM) model was used to simulate the erosion and deposition based on the equation for the mass conservation and momentum conservation while considering the continuity of the fluid. The peak impact force from the debris flow occurred at 0 to 5 sec and 15 to 20 sec. When the supplied water discharge was increased, greater peak impact force was generated at 16 to 19 sec. This means that when increasing the water supply, the velocity of the debris flow became faster, which results in increased energy of the consolidation between the particles of the water and the sediment made. If a number of check dams were to be set up, it would be necessary to investigate the impact force at each location of the check dam. The results of this study could provide useful information in predicting the impact force of the debris flow and in installing the check dams in appropriate locations.

최근 기후 변화에 의한 집중호우는 산지에서 토석류를 발생시켜 많은 피해를 양산하고 있다. 연구의 목적은 토석류 발생 가능성이 높은 산지에 사방댐을 설치하였을 경우, 사방댐의 설치 위치에 따라 공급유량의 변화에 대하여 사방댐이 받는 충격력을 평가한 것이다. 연구방법으로는 수치해석모델을 이용하였고, 수치해석 모델은 침식과 퇴적 모델을 이용하여 유한차분법을 적용하였으며, 사방댐에 영향을 주는 토석류의 충격력은 유체의 연속성을 고려하여, 질량보존법칙과 운동량 보존 법칙을 만족하는 지배 방정식을 이용하였다. 수치모의를 한 결과 토석류는 도달 초기에 충격력의 Peak가 발생하였으며, 16sec~19sec 구간에서도 토석류의 Peak가 발생하였고, 공급유량을 증가시킨 경우 이 구간에서 여러 개의 토석류 충격력의 Peak가 발생하였다. 이는 공급유량의 증대로 인해 토석류의 유하 속도를 증가시키고, 증가된 속도는 물 입자와 토사의 충돌로 인해 에너지가 증대되고 있음을 보여준다. 따라서, 산지에 연속적으로 여러 기의 사방댐을 설치하려고 할 때 각 위치에서 사방댐이 받는 충격력을 조사할 필요가 있다. 본 연구의 결과는 비탈 경사면에서 토석류 제어를 목적으로 설치되는 구조물이 받는 충격력과 사면에서 사방댐의 적정 위치를 설정하는 데 좋은 정보를 제공할 것이다.

Keywords

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Fig. 1. Schematic design for numerical experiment of debris flow

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Fig. 2. Impact Force, Water Velocity, and Water Depth at (a) 6m-location of and (b) 5.5m-location of check dam for Q_inflow=600cm3/sec

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Fig. 3. Impact Force, Water Velocity, and Water Depth at (a) 5m-location of and (b) 4.5m-location of check dam for Q_inflow=600cm3/sec

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Fig. 4. Impact Force according the location of check dam for Q_inflow=600cm3/sec

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Fig. 5. Impact Force, Water Velocity, and Water Depth at (a) 6m-location of and (b) 5.5m-location of check dam for Q_inflow=700cm3/sec

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Fig. 6. Impact Force, Water Velocity, and Water Depth at (a) 5m-location of and (b) 4.5m-location of check dam for Q_inflow=700cm3/sec

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Fig. 7. Impact Force according the location of check dam for Q_inflow=700cm3/sec

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Fig. 8. Impact Force according the location of check dam for Q_inflow=700cm3/sec (Between 15sec∼20sec)

References

  1. S. Kim, I. Yoon, S. Oh, H. Lee, W. Bae, "Numerical simulation for behavior of debris flow according to the variances of slope angle", Journal of the Korean Geo-environmental Society, Vol.13, No.6, pp.59-66, 2012.
  2. G. B. Crosta, "Failure and Flow Development of a Complex Slide: the 1993 Sesa, landslide", Engineering Geology, Vol. 53, pp. 173-199, 2001. DOI : https://doi.org/10.1016/S0013-7952(00)00073-9
  3. H. Chen, S. Dadson, Y. G. Chi, "Recent Rainfall-Induced Landslides and Debris Flow in Northern Taiwan", Geomorphology, Vol. 77, pp. 112-125, 2006. DOI : https://doi.org/10.1016/j.geomorph.2006.01.002
  4. T. Takahashi. Debris Flow: Mechanics, Prediction and Countermeasures. pp.1-448, Taylor & Francis/Balkema, Tokyo, 2007. DOI: https://doi.org/10.1201/9780203946282
  5. S. B. Savage, K. Hutter, "The Dynamics of Avalanches of Granular Materials from Initiation to Runout. Part I: Analysis", Acta Mechanica, Vol.86, pp.201-223, 1991. DOI: https://doi.org/10.1007/bf01175958
  6. J. S. O'Brien, P. Y. Julien, W. T. Fullerton, "Two-dimensional Water Flood and Mudflow Simulation", Journal of Hydraulic Engineering, Vol.119, No.2, pp.244-266, 1993. DOI: https://doi.org/10.1061/(asce)0733-9429(1993)119:2(244)
  7. R. P. Denlinger, R. M. Iverson, "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, 2001. DOI : https://doi.org/10.1029/2000jb900330
  8. T. Takahashi, H. Nakagawa, T. Harada, Y. Yamashiki, "Routing debris flows with particle segregation", Journal of Hydraulic Engineering, Vol.118, No.11, pp.1490-1507, 1992. DOI : https://doi.org/10.1061/(asce)0733-9429(1992)118:11(1490)
  9. S. Kim, S. Oh, H. Lee, "The Study of Relationship between Bern Width and Debris Flow at the Slope", Korean Geo-environmental Society, Vol.14, No.11, pp.5-12, 2013.
  10. J. Paik, S. Park, "Numerical Modeling and Field Measurement of 1D Debris Flows", Proceeding of the Korean Society of Civil Engineers, Vol.2009, No.10 pp.698-701, 2009.
  11. L. Luzi, F. Pergalani, M. T. J. Terlien, "Slope Vulnerability to Earthquakes at Subregional Scale, using Probabilistic Techniques and Geographic Information Systems", Engineering Geology, Vol.58, No.3-4, pp.313-336, 2000. DOI: https://doi.org/10.1016/S0013-7952(00)00041-7
  12. N. Miyazawa, T. Tanishima, K. Sunada, S. Oishi, "Debris-flow Capturing Effect of a Grid-Type Steel-Made Sabo Dam Using 3D Distinct Element Method", Debis Flow Hazards Mitigation, Proceedings of the Third Conference on Debris-Flow Hazards Mitigation: Mechanics, Prediction, and Assessment, Switzerland, Rotterdam, pp.527-538, 2003.
  13. B. B. Shrestha, "Numerical Modeling on Debris Flows and Its Structural Counter Measure by Sabo Dam", Master's Thesis, Institute of Engineering, Tribhuvan University, Nepal, 2004.
  14. Y. Satofuka, T. Mizuyama, "Numerical Simulation on a Debris Flow in a Mountainous River with a Sabo Dam", Journal of the Japan Society of Erosion Control Engineering, Vol.58, No.1, pp.14-19, 2005. DOI: https://doi.org/10.11475/sabo1973.58.14
  15. H. Gotoh, E. Harada, T. Sakai, K. Goda, "Numerical Simulation of Blocking Process of Grid-Type Dam by Debris Flow", Annual Journal of Hydraulic Engineering, JSCE, Vol.50, pp.739-744, 2006. DOI: https://doi.org/10.2208/prohe.50.739
  16. R. Osti, S. Egashira, "Method to Improve the Mitigative Effectiveness of a Series of Check Dams against Debris Flows", Hydrological Processes, Wiley InterScience, Vol.22, No.26, pp.4986-4996, 2008. DOI: https://doi.org/10.1002/hyp.7118
  17. K. Chun, Erosion Control Engineering, Hyangmunsa, Seoul, 2011. DOI: https://doi.org/10.978.897187/2338
  18. H. Kwon, "Safety Analysis of Check Dam according to Sediment Yield in Gangwon Mountain Region", Journal of Korean Society of Hazard Mitigation, Vol.11, No.5, pp.247-254, 2011. DOI: https://doi.org/10.9798/KOSHAM.2011.11.5.247
  19. C. Lee, S. Joh, K. Park, M. Kim, H. Yoon, A. R. Raja, "Quality Grading of Concrete Soil Erosion Control Dam in the Aspect of Unconfined Concrete Strength by Surface-Wave Technique", Journal of Korean Forest Society, Vol.101, No.3, pp.412-425, 2012.
  20. X. Lin, Y. You, J. Liu, Y. Zhao, "A Tentative Study on the Stability of a Check Dam". WIT Press on Advances in Earth and Environmental Sciences, 2014. DOI: https://doi.org/10.2495/icesep130081
  21. B. Yoon, K. Jun, B. Jun, W. Jung, "A Analysis on the Debris Flow Reduction Effect of Debris Barrier Through Simulation", Journal of Korean Society of Hazard Mitigation, Vol.18, No.2, pp.167-173, 2018 DOI: https://doi.org/10.9798/kosham.2018.18.2.167
  22. S. Kim, K. Chun, S. Kim, K. Jun, "Analysis of Impact Force at the Check Dam For Debris Flow Disaster", Korean Review of Crisis & Emergency Management. Vol.11, No.9, pp.65-77, 2014.