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

Korean Geo-Environmental Society (한국지반환경공학회)
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An Experimental Study on Cylindrical Countermeasures for Dissipation of Debris Flow Energy

원통형 대책 구조물의 토석류의 에너지 저감 효과에 대한 실험적 연구

  • Kim, Beom-Jun (Department of Civil Engineering, Gangneung Wonju National University) ;
  • Han, Kwang-Do (Department of Water Resources, ISAN Corporation) ;
  • Kim, Ho-Seop (Department of Research Institute, ISAN Corporation) ;
  • Choi, Clarence E. (Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology) ;
  • Yune, Chan-Young (Department of Civil Engineering, Gangneung Wonju National University)
  • Received : 2018.10.30
  • Accepted : 2018.11.19
  • Published : 2019.01.01
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Abstract

In this study, to investigate the effect of cylindrical countermeasure on the flow characteristics of debris flow, a series of small-scale tests were conducted using a flume with cylindrical baffles. Various heights and row numbers of installed baffles were considered as a test condition. High speed cameras and laser level sensors were also installed at the top and side of the channel, respectively, to capture the debris flow dynamics before and after baffles. Based on test results, the energy dissipation of debris flow due to baffles was analyzed. Test results showed that baffles can significantly reduce the velocity and flow depth of debris flows. The energy dissipation effect of baffles also increase as the increase of height and row number of baffles.

본 연구에서는 원통형 대책 구조물의 설치변화가 토석류의 흐름에 미치는 영향을 확인하기 위해, 대책 구조물을 설치 가능한 소형수로를 제작한 후에 실내모형실험을 실시하였다. 실험은 수로 내에 설치된 구조물의 높이와 종방향 열의 개수를 변화시켜가면서 수행하였다. 대책 구조물이 설치된 수로 측면과 상부에는 초고속 카메라와 레이저 수위센서를 설치하여, 토석류가 구조물을 통과하기 전 후의 흐름변화를 측정하였다. 이를 바탕으로 대책구조물 설치에 따른 토석류의 에너지 저감효과를 비교, 분석하였다. 실험결과, 원통형 대책 구조물의 설치는 토석류의 유속과 흐름깊이를 감소시키는 것으로 나타났다. 또한 구조물의 설치높이와 종방향 열의 개수가 증가할수록 그 영향은 더욱 커지는 것으로 나타났다.

Keywords

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Fig. 1. Debris flow baffles in Korea

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Fig. 2. Debris flow baffles installed in a basin in front of a rigid barrier in Hong Kong

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Fig. 3. Small-scale test

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Fig. 4. Cylindrical baffles

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Fig. 5. Installation of cylindrical baffles (two rows)

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Fig. 6. Experimental setup

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Fig. 7. Velocity of debris flow

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Fig. 8. Flow depth of debris flow

Table 1. Index properties of Jumunjin sand

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Table 2. Test condition

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Table 3. Comparison of height of baffle and number of baffle rows

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Table 4. Comparison of height of baffle and number of baffle rows

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