Control of Lateral Movement of River Bends by Installing the Floating Vanes

Natural phenomena such as bed scouring in the outer bank and deposition in the inner bank of meandering rivers cause lateral migration of the river bend in the downstream direction. So far, different measures have been developed to control this movement. In the present study, the influences of floating vanes application on bed scouring and deposition in river bend has been investigated experimentally. For this purpose, a physical model of Karoon river 180-degree bend at the south of Ahwaz city was constructed. Also flume bed topography measurement showed that the bend scour had been occurred from 130 degrees’ location to the end of the bend. Therefore, seven floating vanes were installed in series at this bendsegment and tested under three different Froude numbers (=0.18, 0.20 and 0.22). The flow depth was kept constant for these tests. The vanes dimensions were designed according the Odgaard’s recommendations for submerged vanes. Bed topography maps were measured using a laser meter and contour lines were plotted using the Tecplot software. The results showed that with installing floating vanes, the maximum scour depth reduced as much as 50%, 50% and 40% for Froude numbers equal to 0.18, 0.20 and 0.22, respectively. It was also found that generally the scour depth not only was shifted toward the inner bend, sedimentdeposition also was observed at the outer bank.