Hydraulic Forces on Submerged Bridge Decks.

Bridge decks can be subjected to large horizontal forces when overtopped by a flooding waterway. These forces can result in the displacement of bridge decks from the bents. This paper reports on the results of a laboratory study of horizontal forces on simulated bridge decks under submerged, steady flow conditions. An empirical equation was developed that expressesthe dimensionless horizontal force per unit bridge width as a function ofthe approach flow Froude number and dimensionless geometric parameters. The equation was used to determine the resultant horizontal force on a prototype bridge using the output from the Hydrologic Engineering Center's River Analysis System (HEC-RAS Version 3.1.3) one-dimensional, hydraulic model.