연구홍보포털

논문 초록 (Abstract)

The concept of vegetation freeboard equivalence (VFE) is presented from the comparison between the rise in stage with/without vegetation and the freeboard height under design discharge conditions. In South Kor ea, the freeboard height of large, medium andsmall rivers is defined as a function of river discharge. Two models are used for this analysis o f flood stage with and without vegetation: the 1-D model HEC-RAS and t he 2-D model RMA-2. Both models are applied to three river study sites of the Geum River in South Korea as representative sites for a large, a medium and a small river. The analysis shows that without vegetati on, both models provide comparable results and the calculated results are in very good agreement with the design configuration. The vegetat ion effects on the medium river are less significant, and the freeboa rd is adequate to contain the rise in stage from the added floodplain vegetation in large rivers. The concept of vegetation freeboard equivalence is therefore useful for the analysis of flood river stages after the restoration of channels with increased floodplain veg etation.