Water Resources Research Act Program

Details for Project ID 2006OH39B

The Scour and Deposition River and Estuarine Bridges

Institute: Ohio
Year Established: 2006 Start Date: 2006-03-01 End Date: 2008-02-28
Total Federal Funds: $51,562 Total Non-Federal Funds: $107,265

Principal Investigators: Diane Foster, Thomas Lippmann

Project Summary: The scour around bridge foundations is the leading cause of bridge failure in the United States. Unfortunately, our present understanding of flow and sediment transport near structures is not complete enough to make accurate predictions of the geomorphology around bridge piles. This limitation is due to both a lack of concomitant field observations of the flow, sediment transport, and geomorphic bed evolution, and in coupling the observations with numerical fluid-sediment models. The objective of this research is to increase our ability to predict how variations in flow conditions will affect the scour and/or deposition of sediment around estuarine and river bridge piles. Two specific goals for this project are to 1) evaluate an existing three-dimensional flow and sediment transport model with field observations of river morphology and flow velocity, and 2) to examine the effect of variations in river stage on bridge scour. Established field sampling techniques (not previously utilized in work of this type) will be used to make measurements of surface and mid-depth flow velocities, and fine-scale river bed evolution in the immediate vicinity of the piles and larger scale topography within about 500-1000 meters up- and down-stream of the bridge. The coupling of detailed field observations with models should lead to a much improved understanding of the scour process, and we anticipate that these results may be used by engineers, scientists, and managers interested in improved parameterization of the sediment transport around structures. The verified model may also be used to identify locations where bridge scour may be problematic under hypothetical flow conditions, or to assess scour in already identified areas of concern.