Ecology and Resilient Infrastructure

Korean Society of Ecology and Infrastructure Engineering (응용생태공학회)
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Numerical Analysis of the Behavior of Bars in a Compound Channel with a Drop Structure

낙차공이 있는 복단면 수로에서 사주거동의 수치분석

  • Kim, Gi-Jung (Department of Civil Engineering, Korea National University of Transportation) ;
  • Jang, Chang-Lae (Department of Civil Engineering, Korea National University of Transportation)
  • 김기정 (한국교통대학교 토목공학과) ;
  • 장창래 (한국교통대학교 토목공학과)
  • Received : 2016.02.05
  • Accepted : 2016.03.20
  • Published : 2016.03.31
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Abstract

This study investigated the behavior of sediment bars in a compound channel with a drop structure. Flow was separated into side banks by alternate bars, and flow was concentrated into the downstream of bar fronts. The bed downstream of a drop structure degradated due to the concentrated flow from it. Bar shapes were kept by the influence of their shapes upstream. Alternate bars, central bars, and multiple bars were developed as the width to depth ratio increased, and the number of bars increased. The bar in the downstream of a drop structure decreased in length due to the concentration of flow and its disturbance.

본 연구에서는 2차원 수치모형을 이용하여 복단면 하도에서 낙차공을 고려하여 하도 변화와 사주의 거동 특성을 분석하였다. 교호사주에 의하여 흐름이 분리되며, 사주의 선단부에서 흐름이 집중되고 수충부가 형성되었다. 낙차공에 의하여 흐름은 하도 전체에 균등하게 분산되었으며, 낙차공 하류에서는 흐름이 집중되고 하상고가 낮아졌다. 그러나 사주의 형상은 낙차공 상류의 영향을 받아 교호사주의 형상을 유지되었다. 하폭 대 수심이 증가하면서 교호사주, 중앙사주, 복렬사주가 형성되었으며, 사주의 수가 증가하였다. 낙차공에 의하여 흐름이 집중되어 낙차공 상류에서 사주길이보다 낙차공 하류에서 사주길이가 더 짧게 나타났다.

Keywords

References

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