Using a Bed Sill as a Countermeasure for Clear-Water Scour at a Complex Pier with Inclined Columns Footed on Capped Piles

River bridge piers may collapse due to the local scour around their foundations. It is known that an effect of three-dimensional flow field develops near pier and geometric complexity a non-cylindrical may, correspondingly, increase process. also various devices be used as countermeasures. This manuscript explores use bed sill countermeasure for at complex compound array piles, pile cap, two inclined columns with rectangular sections above cap. geometry, never studied before in combination countermeasure, was stimulated by existing bridge. Different placements were tested (at upstream or downstream edges pier, intermediate position) values diameter number, cap thickness elevation. The results wide experimental campaign consistently showed most effective placement transverse edge which reductions up 30–40% could obtained long-term depth. performance decreased about 10% when placed pier. Furthermore, installation changed shape hole because then located area prone scour; however, present experiments, effects beneficial terms resulting Although investigation single hydro-dynamic condition prevents findings from being generalized, promising stimulate further consideration