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2018 Vol.51, Issue 9 Preview Page

Research Article

Experimental analysis of the sedimentation processes by variation of standing angle in the improved-pneumatic-movable weir

실내실험에 의한 가동보 기립각도 변화에 대한 토사의 퇴적 과정 분석

Kyung Su Leea
,
Chang-Lae Jangb*
이 경수a
,
장 창래b*
aNational Disaster Management Institute, Ministry of the Interior and Safety
bDepartment of Civil Engineering, Korea National University of Transportation
a행정안전부 국립재난안전연구원
b한국교통대학교 토목공학과
* Corresponding Author
30 September 2018. pp. 795-802
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Abstract

`This study investigates the hydraulic characteristics and the delta development processes in the improved-pneumatic-movable weir by considering the standing angle of the weir through laboratory experiments. The delta migration speed decreases rapidly with time. As the ratio of delta height to water depth increases, the dimensionless delta migration speed decreases at the delta point. Therefore, the water depth decreases as the delta height increases. Although the delta volume is large due to the effective height of the delta, the delta migration speed and sediment deposition decreases because of the backwater effect on the delta. On the same bed slope condition, the larger the weir height, the larger the delta volume and the ratio of delta height to delta front length is close to 1.0. The delta development could be suppressed when the weir is high. Therefore, the condition that the weir is high has the suppressing effect on the delta developments.

Keywords
Delta
Movable weir
Reservoir sedimentation
Sediment processes
Standing angle of weir

본 연구에서는 실내실험을 통하여 개량형 공압식 가동보를 대상으로 보의 기립각도를 고려한 유사의 퇴적과 델타의 발달 과정을 파악하였다. 가동보 상류에서 유입되는 유사는 배수의 영향으로 유속이 느려지면서 퇴적이 되고 델타가 형성되며 하류로 이동하였다. 각 실험조건에 대하여 시간에 따른 델타의 이동속도는 델타는 시간이 지나면서 현저하게 감소하고, 보에 접근하였다. 무차원 델타의 높이(hd/h)가 증가할수록 무차원 델타의 이동속도(SD/V0)는 감소하였다. 따라서 델타의 높이(hd)가 증가할수록 수심(h)은 감소하였다. 델타의 유효높이(hw)가 크기 때문에 델타의 체적(VxD)은 증가하지만 배수(backwater)의 영향을 받아 델타의 이동속도(SD)와 퇴적량은 감소하였다. 수로 경사가 일정할 때, 보의 높이(W)가 클수록 델타체적(VxD)이 증가하고, 델타의 전면부 길이비(hd/𝛥S)는 1에 가깝다. 같은 유량조건인 경우에 가동보의 기립 각도가 가장 클 때, 시간당 델타의 퇴적량(Qs)은 가장 작았다. 따라서 보의 높이(W)가 클수록 델타의 발달을 억제할 수 있는 효과가 크다.

키워드
델타
가동보
저수지 퇴사
퇴적 특성
보의 각도
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Information
  • Publisher :KOREA WATER RESOURECES ASSOCIATION
  • Publisher(Ko) :한국수자원학회
  • Journal Title :Journal of Korea Water Resources Association
  • Journal Title(Ko) :한국수자원학회 논문집
  • Volume : 51
  • No :9
  • Pages :795-802
  • Received Date : 2018-06-06
  • Revised Date : 2018-07-12
  • Accepted Date : 2018-07-30
  • DOI :https://doi.org/10.3741/JKWRA.2018.51.9.795
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