A Study on Interaction between Overfall Types and Scour at Bridge Piers with a Moving-Bed Experiment

River slopes can be changed due to an extreme event, e.g., a large-scale earthquake. This uplift riverbed greatly and thereby change the behavior of river flow into free or submerged overfall. Corresponding damage, including erosion, on bridge piers located in take place aforementioned conditions. A reconstructed pier same location would also experience similar impact if condition is not changed. It important identify these phenomena research mechanism interaction between overfall types scour at piers. Therefore, this paper aimed studying impacts with different distances by series moving-bed experiments. The experiment results showed clearly that protection requires attention particularly when maximum hole induced z directional eddies. In many other cases, such as was upstream slope drop, deposition mound could observed back pier. indicates that, while location, additional takes