Journal of Korean Society of Disaster and Security (한국방재안전학회논문집)

Korean Society of Disaster & Security (한국방재안전학회)
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The Experimental Study for Variance of Sediment Volume Concentration of Debris Flow due to Damped Structures

감쇠 구조물에 의한 토석류 토사체적 농도 변화에 관한 실험적 연구

  • Youngdo Choi (School of Civil Engineering, Chungbuk National University) ;
  • Sungduk Kim (School of Civil Engineering, Chungbuk National University) ;
  • Hojin Lee (School of Civil Engineering, Chungbuk National University)
  • Received : 2023.12.05
  • Accepted : 2023.12.19
  • Published : 2023.12.31
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Abstract

The purpose of this study is an experimental research to investigate the effectiveness of debris flow reduction structures when a debris flow disaster occurs on a steep slope. The control structure for debris flow took the form of baffle, and the soil deposition area and soil runout distance due to debris flow from the downstream were investigated according to the installation number of baffle and each specification. As the slope of the channel became steeper, the sediment deposition area and runout distance increased, and as the sediment volume concentration decreased, the sediment deposition area and runout distance increased. When the sediment concentration was low, differences appeared depending on the slope of the channel because the debris flow had a high liquid content. Overall, the larger the sediment volume concentration, the greater the decrease in sediment deposition area and soil runout distance. As the number of baffles increases, the soil deposition area and runout decrease, showing that the baffles have the ability to control debris flows. The results of this research will provide good information when installing attenuation or control structures when sediment disasters occur in steep slopes.

본 연구의 목적은 급경사지 사면에서 토석류 재해가 발생했을 때, 토석류 저감 구조물의 효과를 조사한 실험연구이다. 제어 구조물로는 베플 형태를 취하였고, 베플의 설치 기수와 각 제원에 따라서 하류에서의 토석류에 의한 토사퇴적면적과 토사도달거리를 조사한 것이다. 수로의 경사가 급할수록 토사의 퇴적면적과 도달거리가 증가하였고, 토사체적농도가 감소할수록 토사퇴적면적과 토사의 도달거리가 증가하였다. 토사농도가 작은 경우(Cv = 0.5)는 토석류의 액성이 크기 때문에 수로 경사에 따른 차이가 나타났고, 전반적으로 토사체적농도가 클수록 토사퇴적면적과 토사의 도달거리 감소율이 크게 나타났다. 베플의 수를 증가할수록 토사퇴적면적과 도달거리를 약 5~10% 이상 감소하는 것으로 나타남으로서 베플의 토석류 제어능력이 있음을 보여주고 있다. 본 연구의 결과는 급경사지에서 토사재해가 발생할 때 감쇠 또는 제어 구조물을 설치할 때 중요한 정보를 제공할 것이다.

Keywords

Acknowledgement

This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (No. 2021R1l1A3054408).

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