Control of River Bend Migration Using Permeable Rectangular Vane Made by Six-Pillar Concrete Elements

Controlling the bends migration in the large meandering rivers using common groins is too costly, time consuming and needs some types of river by passing. Developing deep scour around nose of groins can lead to failure of the structure. However, it is necessary to investigate the new measures and materials to have less scour and to easily be installed, respectively. The six-pillar concrete (SPC) element is one of the materials which have been used successfully in bridge scour control. By constructing rectangular vane with SPC elements (RV-SPC) can take advantage of both economy and scour mitigation. In the present experimental study, the application of new technique has been studied. Tests were carried out at 180° flume bend for high flow condition (Froude number = 0.263). Two series of tests were carried out: (1) the base line tests without installing RV-SPC and (2) with RV-SPC at various intervals (5 L , 6 L , 7 L , 8 L ) with the effective length equal to 20% of flume width ( L = 12 cm). By comparing the results of two series of tests, it was determined that by installing RV-SPC at interval of 6 L from each other, the maximum scour depth around the structure is reduced up to 70.0%.