Ecology and Resilient Infrastructure

Korean Society of Ecology and Infrastructure Engineering (응용생태공학회)
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Sensitivity Analysis on Flood Level Changes by Offline Storage Creation Based on Unsteady Flow Modeling

부정류 모의 기반 오프라인 저류지 조성에 따른 홍수위 변화 민감도 분석

  • Eun-kyung Jang (Department of Hydro Science and Engineering Research, Korea Institute of Civil Engineering and Building Technology) ;
  • Un Ji (Department of Hydro Science and Engineering Research, Korea Institute of Civil Engineering and Building Technology) ;
  • Sanghyeok Kim (Department of Water Resources, Isan Corporation) ;
  • Jiwon Ryu (Civil and Environmental Engineering, KICT School, University of Science and Technology)
  • 장은경 (한국건설기술연구원 수자원하천연구본부 ) ;
  • 지운 (한국건설기술연구원 수자원하천연구본부) ;
  • 김상혁 ((주)이산 수자원부 ) ;
  • 류지원 (과학기술연합대학원대학교 건설환경공학)
  • Received : 2023.12.11
  • Accepted : 2023.12.22
  • Published : 2023.12.31
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Abstract

This study analyzed the effect of flood level reduction in the case of creating and operating offline storage for the Jangdong district, which can be used as a flood buffer space for the Geumgang River, through one-dimensional unsteady flow numerical simulation. In particular, the sensitivity analysis of changes in the height and width (length) of transverse weirs on flood level changes was performed to provide quantitative information necessary for flood control facility (embankment) design. As a result of analyzing the flood control effect of the offline storage based on the peak flood discharge and level, spatially, the flood control effect at the planned flood buffer space site and the downstream end was confirmed, and it was confirmed that the flood reduction effect at the downstream occurred the most. By design conditions of the transverse overflow weir, the greatest flood reduction effect was found under the condition that the overflow weir height based on the 50-year frequency flood level and the transverse overflow weir width (length) of 125 m were considered. The effect of delaying the time to reach the maximum flood due to the operation of the offline storage site was also presented based on unsteady flow modeling.

본 연구에서는 금강 장동지구를 대상으로 홍수완충공간을 오프라인 저류지로 조성하여 운영하는 경우에 대해 홍수위 저감 효과를 1차원 부정류 수치모의를 통해 분석하였다. 특히 오프라인 저류지의 횡월류 위어 높이와 폭 (길이)의 변화에 따른 수위변화의 민감도를 분석하여 홍수관리시설 (제방) 설계에 필요한 정보를 정량적으로 제공하였다. 첨두 홍수량 및 홍수위를 기준으로 오프라인 저류지의 홍수조절효과를 분석한 결과, 공간적으로는 홍수완충공간 조성 예정지와 하류구간에서 홍수조절효과가 확인되었으며, 특히 하류에서 가장 큰 홍수저감 효과가 나타나는 것을 확인할 수 있었다. 횡월류 위어의 설계 조건별로는 50년 빈도 홍수위 기준의 월류고와 125 m의 횡월류 위어 폭 (길이)을 고려한 조건에서 가장 큰 홍수저감 효과가 나타났다. 오프라인 저류지 조성으로 최대홍수량 도달 시간이 지연되는 효과 또한 부정류 모의를 통해 제시하였다.

Keywords

Acknowledgement

본 논문은 환경부의 재원으로 한국환경산업기술원의 기후변화대응환경기술개발사업의 지원을 받아 연구되었습니다 (과제번호 022003460002).

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