Suitable Bridge Pier Section for a Bridge over a Natural River

Estimation of maximum scour depth at the bridge pier is necessary for the safety and economy of the bridge design. Therefore, the phenomenon of scour around bridge piers was extensively studied from the literature to find the effect of pier shapes and inclined flow on scour depth at bridge piers.

It was found from the analysis that scour depth increases with the increase of the flow angle relative to the pier axis, but for a cylindrical pier, maximum scour depth does not change with flow angle. When the flow angle is at 300, the scour depth for the cylindrical pier is smaller than other pier shapes; hence circular pier shape is more suitable for natural rivers which have possibility of changing flow direction.