MODEL FOR PREDICTING FLUSHING FUNCTION OF SAND BAR IN SET-BACK TYPE FLOODWAY

Abstract

 In a set-back type floodway, the opening of the floodway is located landward of the berm top, and sand deposition into the floodway could be reduced, which in turn is useful to enhance the safty during a flood. Regarding the beach changes around this type of the floodway, a model was proposed on the basis of the contour-line change model, taking the reduction of the equilibrium slope when seaward currents occur into account. The effect of the seaward currents from the floodway was included in the model, and the calculation results were compared with the results of the movable-bed experiment. The calculated results explained well the experimental results.