Abstract: The local scour of tower footing (pier) is a critical subject in planning and designing river-crossing project. Skewed tower footing has being gradually used in river-crossing engineering due to special geography, geology and economic conditions. But researchers paid more attention to the local scour of orthogonal tower footing (pier) rather than that of skewed tower footing. In this article, the rules of local scour of a skewed tower footing are researched through generalized model test. Results reveal that the increment of flow velocity on deviational side of skewed tower footing is bigger than that on dorsal side; the maximum scour depth is large, and the position is on deviational side; the scour pit displays an asymmetrical horseshoe shape, and the scour range on deviational side is larger than that on dorsal side. When bed surface around the tower footing is protected, this trend becomes weak. The results offer reference for researches on the local scour of skewed tower footing of river-crossing bridge or cable gallery construction.

Key words: skewed tower footing, pile group, scour pit, scour depth, flow velocity