Journal of Korea Water Resources Association (한국수자원학회논문집)

Korea Water Resources Association (한국수자원학회)
권호 표지
DOI QR코드

DOI QR Code

Analysis of Long-Term Riverbed-Level and Flood Stage Variation due to Water Gate Operation of Multi-functional Weirs at Geum River

다기능보의 수문운영에 따른 금강의 장기하상변동 및 홍수위변화 분석

  • 정안철 (충남대학교 공과대학 토목공학과) ;
  • 정관수 (충남대학교 공과대학 토목공학과)
  • Received : 2014.12.04
  • Accepted : 2015.04.03
  • Published : 2015.05.31
Download PDF
⟨ Previous Next ⟩

Abstract

Multi-functional weirs has been installed in four rivers are hydraulic structures across the river. The structures were divided into movable and fixed weirs. Hence, riverbed-level variation and sediment transport can be varied due to water gate operation. In this study, the long-term riverbed-level variation of Geum river basin due to water gate operation of multi-functional weirs was studied. Result of this study shows that the variation of thalweg elevation was greater than the variation of annual average riverbed elevation due to multi-functional weirs construction and water gate operation. Maximum riverbed degradation of thalweg elevation that occurred was 2.79m and riverbed aggradation was 1.90m. Maximum riverbed degradation of the annual average riverbed elevation that occurred was 2.16m and riverbed aggradation was 1.24m. Analysis result of flood stage by the variation of riverbed-level shows that flood stages were increased in majorities area. The maximum increase in the value of flood stage was 2.23m. For this reason, flood stages can be greater than the freeboard of the levees. Therefore, we should consider the water gate operation of multi-functional weirs when planning and managing sediment in the river. We are expecting to use the result of this study in river planning for river management and selecting the river regime.

국내 4대강에 설치된 다기능보는 하천을 횡단하는 수공구조물로써 고정보와 가동보로 구분되어 설치되었으며, 각 다기능보의 수문운영 방식에 따라 유량이 변화하여 하상변동 및 유사이동 형태의 변화 가능성이 있다. 본 연구에서는 다기능보의 수문운영에 따른 장기 하상변동을 금강유역을 중심으로 연구하였다. 연구결과, 금강에서는 다기능보의 설치 및 수문운영 시나리오에 따라서 최심하상고의 변화가 연평균하상고의 변화에 비해서 상대적으로 큰 것으로 나타났다. 최심하상고의 하상저하는 최대 2.79 m, 하상상승은 최대 1.90 m까지 발생하는 것으로 나타났으며, 연평균하상고의 하상저하는 최대 2.16 m, 하상상승은 최대 1.24 m까지 발생하는 것으로 나타났다. 또한 하상변동에 따른 홍수위 분석 결과, 다기능보 설치 후에 홍수위가 대부분 상승하는 것으로 나타났으며, 최대 2.23 m까지 상승하는 것으로 나타났다. 이러한 결과로 인해서 제방의 여유고를 상회하는 홍수위가 발생할 가능성이 있기 때문에, 하천의 유사관리 및 하천계획수립을 함에 있어서 다기능보의 수문운영을 고려해야 한다고 판단된다. 또한 본 연구결과는 향후 하천계획을 수립함에 있어서 종단적 하도관리 및 안정하상 채택 등을 위해서 기초자료로 활용될 수 있을 것으로 본다.

Keywords

References

  1. Ahn, J.M., and Lyu, S. (2013). "Analysis of flow and bed change on hydraulic structure using CCHE2D:focusing on Changnyong-Haman." Journal of KWRA, KWRA, Vol. 46, No. 7, pp. 707-717.
  2. Choi, M., Lee, S.O., Ahn, J.H., and Yoon, Y.N. (2008). "An analysis of long-term river bed changes using surface-water modeling system(SMS) model: a case study of Pochon stream basin." Journal of KOSHAM, KOSHAM, Vol. 8, No. 2, pp. 139-147.
  3. Chung, S.Y., Park, B.J., and Jung, K.S. (2006). "A study on the applicability of GSTAR-1D to the riverbedlevel variation in the Geum river." Proceedings of the KWRA Conference, pp. 1611-1615.
  4. Jang, C.L., and Woo, H. (2009). "Analysis of bed material changes by flushing flow from Daecheong dam." Journal of KWRA, KWRA, Vol. 42, No. 10, pp. 845-855.
  5. Ji, U., Son, K.I., and Kim, M. (2009). "Numerical analysis for bed changes in the upstream channel due to installation of sediment release openings in the flood control dam." Journal of KWRA, KWRA, Vol. 42, No. 4, pp. 319-329.
  6. K-water. (2012). Dam operational practices handbook.
  7. KWRA(Korea Water Resources Association) (2009). Standard and commentary of river design.
  8. MLTMA(Ministry of Land, Transport and Maritime Affairs) (2009). Geumriver basin master plan (Changed).
  9. MLTMA(Ministry of Land, Transport and Maritime Affairs) (2010). Annual hydrological report on Korea.
  10. MOCT(Ministry of Construction and Transportation) (2006). Survey report of Geum river basin.
  11. NIER (National Institute of Environmental Research) (2010). The prediction of riverbed change, sediments and dredging period after building gydraulic structures in the Geum river, 2010-91-1266.
  12. Shen, H.W. (2010). "Flushing sediment through reservoirs." Journal of Hydraulic Research, IAHR, Vol. 37, No. 6, pp. 743-757. https://doi.org/10.1080/00221689909498509
  13. Son, A., Han, K., and Kwon, T. (2013). "The study of bed change and stability depending on hydraulic structure." Journal of KOSHAM, KOSHAM, Vol. 13, No. 3, pp. 157-166.
  14. USACE(US Army Corps of Engineers). (2010). HECRAS river analysis system user's manual version 4.1, CPD-68, California, pp. 623-631.
  15. Wang, Z.Y., Wu, B., and Wang, G. (2007). "Fluvial processes and morphological response in the Yellow and Weihe river to closure and operation og Sanenxia dam." Geomorphology, Elsevier, Vol. 91, pp. 65-79. https://doi.org/10.1016/j.geomorph.2007.01.022
  16. Wu, B., Wang, G., and Xia, J. (2007). "Case study: delayed sedimentation response to inflow and operations at Sanmenxia dam." Journal of Hydraulic Engineering, ASCE, Vol. 133, No. 5, pp. 482-494. https://doi.org/10.1061/(ASCE)0733-9429(2007)133:5(482)
  17. Yeon, K.S., Jeong, S.M., Yun, C.Y., Lee, J.H., and Shin, K.S. (2009). "A riverbed change prediction by rivercrossing structure-focused on the major river reaches of the multifunctional administrative city-." Journal of KOSHAM, KOSHAM, Vol. 9, No. 1, pp. 107-113.
  18. Yu, K. (2011). "New concept of average river bed and general trend of river bed change in the Nakdong river." Journal of KCA, KCA, Vol. 11, No. 6, pp. 486-494.
  19. Ziegler, C., and Nisbet, B. (1995). "Long-term simulation of fine-grained sediment transport in large reservoir." Journal of Hydraulic Engineering, ASCE, Vol. 121, No. 11, pp. 773-781. https://doi.org/10.1061/(ASCE)0733-9429(1995)121:11(773)

Cited by

  1. A Plan for an Assessment of Drop Structure and Levee Design Using HEC-RAS and HEC-6 vol.16, pp.2, 2016, https://doi.org/10.9798/KOSHAM.2016.16.2.445
  2. Analysis on the sediment sluicing efficiency by variation of operation water surface elevation at flood season vol.49, pp.12, 2016, https://doi.org/10.3741/JKWRA.2016.49.12.971
  3. Estimation of River Dredging Location and Volume Considering Flood Risk Variation Due to Riverbed Change vol.18, pp.3, 2018, https://doi.org/10.9798/KOSHAM.2018.18.3.279