Journal of Environmental Science International (한국환경과학회지)

The Korean Environmental Sciences Society (한국환경과학회)
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Sensitivity of Riverbed Characteristics of Valley Area to Hydrologic Factors

계곡부의 하상 특성이 수문 인자에 미치는 민감도 분석

  • Myoung-Ho Son (Department of Civil Engineering, Daegu University) ;
  • Khil-Ha Lee (Department of Civil Engineering, Daegu University)
  • 손명호 (대구대학교 일반대학원 토목공학과) ;
  • 이길하 (대구대학교 일반대학원 토목공학과)
  • Received : 2024.04.24
  • Accepted : 2024.06.03
  • Published : 2024.07.31
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Abstract

This study examined the effects of riverbed slope and roughness coefficient on flood level and flow velocity. A numerical experiment was conducted by installing HEC-RAS in the valley of a sub-basin in Geochang-gun, Gyeongsangnam-do. For each basin, three slopes of riverbeds (slopes-15.0%, 5.0%, and 1.0%) were chosen with different characteristics, and four coefficients of roughness were applied to each slope to parameterize the flow. Flow velocity and flood level were intensively investigated. It was found that in the cases of 15.0% and 5.0%, where the riverbed slopes are steep, the slope dominates the change in flow velocity and flood level, while in the case of 1%, where the riverbed slope is small, the change in flow velocity and flood level caused by changes in roughness coefficient is insignificant. Usually, the riverbed slope is large in the valley part of the watershed, so in this case, the slope will play a dominant role in the results of flow velocity and flood level when designing water-related structures.

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References

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