감조하천 홍수위 계산의 불확실성과 저감 대안 - 임진강 하류를 대상으로 = Uncertainty of Evaluating Design Flood and Mitigation Plan at Downstream of Imjin River

다국어 초록 (Multilingual Abstract)

Compared with general rivers, fluctuations of the water level and the river bed are severe in the tidal river. In hydro-dynamic aspect, such fluctuation gives different river-bed data to us according to observing period. The time-dependent river-bed data and pre-estimation of the Manning's roughness coefficient which is the key factor of numerical modelling induces uncertainty of evaluating the design flood level. Thus it is necessary to pay more attention to calculate the flood level at tidal rivers than at general rivers. In this study, downstream of the Imjin River where is affected by tide of the West Sea selected as a study site. From the numerical modelling, it was shown that the unsteady simulation gave considerable mitigation of the water level from the starting point to 15 km upstream compared to the steady simulation. Either making a detention pond or optional dredging was not effective to mitigate the flood level at Gugok - Majung region where is located in the downstream of the Imjin River. Therefore, a more sophisticated approach is required to evaluate the design flood level estimation before constructive measures adopted in general rivers when establishing the flood control plan in a tidal river.

참고문헌 (Reference)

1 박창근, "임진강 하류 감조구간에서 홍수위 산정 재고" 한국수자원학회 50 (50): 617-625, 2017

2 백경오, "수중보 이설 및 변형에 따른 한강 하구 흐름 특성" 대한토목학회 31 (31): 109-119, 2011

3 Ministry of Land, Infrastructure and Transport, "Report on Riverbed Change at Han River Estuary" 2005

4 Ministry of Land, Infrastructure and Transport, "Report on Environmental Effects due to Dredging at Downstream of Limjin River" 2014

5 K. O. Baek, "Is the Flood Level Mitigated by the Dredging of Limjin River Estuary?" 3 (3): 10-23, 2015

6 Ministry of Land, Infrastructure and Transport, "Imjin River Basic Plan Report" 2011

7 Ministry of Land, Infrastructure and Transport, "Imjin River Basic Plan Report" 2001

8 Ministry of Land, Infrastructure and Transport, "Han River Basic Plan Report" 2002

9 R. H. Khatibi, "Friction Parameters for Flow in Nearly Flat Tidal Channels" 126 (126): 741-749, 2000