Experimental Study on Local Scour in the Downstream Area of Low Drop Structure Types
- 1 Department of Water Resource Research, Korea Institute of Construction Technology, Ilsan, Korea
- 2 Department of Water Resource Research, Korea Institute of Construction Technology, Ilsan, Korea
- 3 Department of Water Resource Research, Korea Institute of Construction Technology, Ilsan, Korea
Abstract
Although ecologically disadvantageous since a river is interrupted because of drop structure installation, such structure installation is also deemed ecologically advantageous in terms of scour and complex flows in the direct downstream area. This study started from the premise that scour hole carries value as a habitat and sought to analyze quantitatively the local scour adjustment possibility in the downstream area through drop structure type change and to offer a habitat through scouring. This study provided changes in drop structure types, such as straight line type and V type. For local scour analysis impacting the downstream area by drop structure type, quantitative analysis of scour scope, depth, and length was comparatively performed for a tentative physical habitat through hydraulic experiments. As a result of the experiments, this study found that scour scope increases and various water depth conditions are offered as the angle of the drop structure’s apex becomes smaller. Future studies accompanied by various fish habitation evaluations are considered useful in finding an alternative to upgrade the ecological environment.
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