Case Study: Hydraulic Model Study for Abandoned Channel Restoration

Abstract

Recently, a paradigm of river restoration is recognized as the importance of flood plan involving abandoned channel. Hence, effort which abandoned channel area by improvement project will become the territory of river area is trying. This study is a part of river restoration project. In this study, hydraulic model experiment and numerical simulation were performed to understand the flow characteristic and bed change for abandoned channel restoration. The target area of the hydraulic model was the midstream of the Hampyeong Stream (stream length: 1.3 km). Horizontal scale was 1/50 and vertical scale was 1/40. For numerical simulation, the FESWMS model was used. Cases of hydraulic and numerical models were frequency flood discharge (50 and 100 years) and channel formation discharge (100 m3/s and 120 m3/s). Flow characteristics were analyzed in fixed condition using hydraulic and numerical models. Bed change on abandoned channel restoration was analyzed on deposition trend using sediment supply from upstream in hydraulic model, and was compared with results of bed shear stress in numerical model. Results velocity profile and bed shear stress of numerical model were similar with trends of measured velocity and deposition of hydraulic model. The results of this study will be applied to restoration design of abandoned channels.