Bridge Abutment Scour in a Floodplain

Recent bridge failures due to pier and abutment scour have reinforced the need for better methods of scour prediction. This paper addresses the problem of prediction of clear-water scour at an abutment which terminates in the floodplain of a compound channel. An experimental study was conducted in a wide flume with a defined main channel adjoining a floodplain with movable bed. A proposed relationship for the abutment scour depth is suggested from dimensional analysis, and it is shown from a regression analysis that the scour data are well represented by the proposed relationship.