Mohammad Vaghefi

Bridge piers are highly susceptible and sensitive to scouring effects, so careful determination of scour depth can ultimately lead to more properly designed pier foundation. The goal of this study is to evaluate scour depth and location around an inclined cylindrical bridge pier in the apex of a sharp 180-degree bend, and also to compare the results with that obtained for a vertical pier. The flume used for the experiments was one metre wide and had a central radius-to-width ratio of two. The results of this study showed that the highest and the lowest scour depth were formed around the pier inclined towards the outer bank and the inner bank, respectively. The highest and lowest scour to flow depth ratios were 1.05 and 0.70 at the upstream straight path. Placing the pier with its inclination towards the outer bank led to the formation of alternating sedimentary dunes at the downstream side of the pier in an area adjacent to the inner bank. Placing the pier with its inclination towards the upstream, downstream, and inner bank led to the formation of only one sedimentary dune with a peak height of 0.60, 0.60, and 0.55 times the flow depth of the entrance section, respectively.