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Analysis of Hydraulic Characteristics of Flood Plain Using Two-Dimensional Unsteady Model

2차원 부정류 모형을 이용한 둔치의 수리특성 분석

  • 구영훈 (인제대학교 환경공학과) ;
  • 송창근 (서울대학교 건설환경공학부) ;
  • 김영도 (인제대학교 환경공학과(낙동강유역환경연구센터)) ;
  • 서일원 (서울대학교 건설환경공학부)
  • Received : 2013.01.27
  • Accepted : 2013.04.04
  • Published : 2013.05.30

Abstract

Since the cross-sectional shape of the Nakdong river is compound type, the water stage rises up to the top of the flood plane, as the flow discharge increases during the extreme rain storm in summer. The recent increase of rainfall intensity and flood frequency results in the immersions of parks and hydrophilic facilities located in the flood plain. Therefore it is necessary to analyze the hydraulic characteristics evolved by the extreme rain storm in the flood plain. The study reach ranging from the Gangjeong Goryeong Weir and the Dalseong Weir, where several hydraulic facilities are located along the channel, was selected and numerical simulations were conducted for 42 hours including the peak flood of the typhoon Sanba. The 2-D transient model, FaSTMECH was employed and the accuracy of the model was assessed by comparing the water level between the simulation results and the measured ones at a gauging station. It showed a high correlation with $R^2$ of 0.990, AME of 0.195, and RMSE of 0.252. In addition, the inundation time, the inundation depth, the inundation velocity, and the shear stress variation in the flood plain facilities were analyzed.

낙동강의 횡단면은 복단면 형태를 띄고 있으므로, 여름철 집중호우에 의해서 하천유량이 증가하면 둔치 상부까지 하천수위가 상승하는 특징이 있다. 또한 최근 강우강도 및 홍수 빈도의 증가로 인해 관련 피해가 급증하고 있으며, 이는 홍수터에 설치된 공원과 같은 친수시설들의 침수피해와 직접적으로 연관되므로, 극한강우 시 둔치에서의 수리학적 영향분석이 필요하다고 판단된다. 본 연구에서는 다양한 친수시설들이 조성되어 있는 강정고령보와 달성보 사이를 모의구간으로 선정하여 태풍 산바에 의해 첨두홍수량이 발생한 시점을 전후로 총 42시간에 걸친 수치모의를 실시하였다. 2차원 부정류 모형인 FaSTMECH 모의결과와 수위관측소에서 실측된 실측수위와 비교하여 모형의 적용성을 검토한 결과 $R^2$는 0.990, AME는 0.195, RMSE는 0.252로 높은 상관관계를 보였다. 그리고 검증된 FaSTMECH 모형을 이용하여 태풍 사상 시 홍수터 내에 위치해 있는 캠핑장과 생태공원 등과 같은 친수시설이 침수되는 시간 및 침수심, 침수 유속 및 전단력 등을 분석하였다.

Keywords

References

  1. Adeff, S. E., and Wang, S. S. Y. (1985). "Hydro-dynamic model for river flow in a microcomputer." Hydraulics and hydrology in small computer age, ASCE, pp. 1017-1023.
  2. Ahn, K. H., Choi, G. W., Jo, H. G., and Jo, S. U. (2009). "Study for influence by installing structures at lower the Han." Proceedings of 2009 KWRA Spring Meeting, Journal of Korea Water Resources Association, pp. 718-722 (In Korean).
  3. Ali, O. A., and Ben, C. Y. (1981). "Diffusion-wave flood routing in channel networks." Journal of Hydraulics Division, ASCE, Vol. 107, No. HY6, pp.719-732.
  4. Choi, G. W. (1991). Hydrodynamic network simulation through channel junctions, Ph.D. Dissertation, Colorado State University, Ft. Collins, CO.
  5. Choi, S. Y., Nam, K. Y., and Han, K. Y. (2011). "Assessment for characteristics of flow according to installing hydraulic structures by 2-D numerical model." Journal of Environmental Impact Assessment, Vol. 20, No. 6, pp.797-813 (in Korean).
  6. Jeon, G. S. (1998). "Quasi-two-dimensional model for floodplain flow simulation." Journal of Korea Water Resources Association, Vol. 31, No. 5, pp. 515-528 (in Korean).
  7. Kim, S. H., Choi, S. Y., Oh, H. W., and Han, K.Y. (2009). "Development of grid reconstruction method to simulate drying/wetting in natural rivers ( I ) : Model Development and Verification." Journal of Korea Water Resources Association, Vol. 42, No. 11, pp. 973-988 (in Korean). https://doi.org/10.3741/JKWRA.2009.42.11.973
  8. Kim, S. Y. (2002). Analysis of flow characteristics by the Tide Influence in Singok Inline-weir, MSc Thesis, Kyonggi University (in Korean).
  9. Lee, J. H., Kim, K. T., and Shim, M. P. (1996). "Finite volume method for two-dimensional unsteady flow in open channel." Journal of Korea Water Resources Association, Vol. 29, No. 5, pp. 173-184 (in Korean).
  10. MLTM (Ministry of Land, Transport and Maritime Affairs) (2009). Nakdong river basin river master plan report (Change), Technical Report (in Korean).
  11. Nelson, J. M., and McDonald, R. R. (1996). Mechanics and modeling of flow and bed evolution in lateral separation eddies, Rep. to Grand Canyon Monitoring and Research Center.
  12. Nelson, J. M., Bennett, J. P., and Wiele, S. M. (2003). Flow and sediment transport modeling tools in fluvial geomorphology, pp. 539-576, Wiley, England.
  13. Nelson, J., Mcdonald, R. R., and Kinzel, P. (2006). "Morphologic evolution in the USGS surface-water modeling system." Journal of Federal Interagency Sedimentation Conference (8th FISC), pp. 233-240.
  14. Sato, S., Imamura, F., and Shuto, N. (1989). "Numerical simulation of flooding and damage to houses by the Yoshida River due to Typhoon No. 8610." J. Natura Disaster Science, Vol. 11, No. 2, pp. 1-19 (in Japanese).
  15. Seo, I. W., and Song, C. G. (2010). "Development of 2D finite element model for the analysis of shallow water flow." Journal of Korean Society of Civil Engineers, Vol. 30, No. 2B, pp. 199- 209 (in Korean).
  16. Seo, I. W., and Song, C. G. (2010). "Specification of wall boundary conditions and transverse velocity profile conditions in finite element modeling." Journal of Hydrodynamics, Vol. 22, No. 5, pp. 633-638. https://doi.org/10.1016/S1001-6058(10)60006-6
  17. Seo, I. W., and Song, C. G. (2012). "Numerical simulation of laminar flow past a circular cylinder with slip conditions." International Journal For Numerical Methods In Fluids, Vol. 68, pp. 1538-1560. https://doi.org/10.1002/fld.2542
  18. Song, C. G., and Seo, I. W. (2012). "Numerical simulation of convection-dominated flow using SU/PG scheme." Journal of Korean Society of Civil Engineers, Vol. 32, No. 3B, pp. 175-183 (in Korean).
  19. Song, C. G., Seo, I. W., and Kim, Y. D. (2012) "Analysis of secondary current effect in the modeling of shallow flow in open channels." Advances in Water Resources, Vol. 41, pp. 29-48. https://doi.org/10.1016/j.advwatres.2012.02.003
  20. Vreugdenhul, C. B., and Wijbenga, J. H. A. (1982). "Computation of flow patterns in river." Journal of Hydraulics Division, ASCE, Vol. 108, No. HY11, pp. 1296-130.
  21. Yong, C. J. (2003). Comparison analysis of river flow models and sediment transport models, MSc Thesis, Honam University (in Korean).
  22. Yoon, T. H. (1982) "Sediment transport prediction model in a harbor by finite element method." Journal of Korean Society of Civil Engineers, Vol. 2, No. 2, pp. 847-587 (in Korean).

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