A heretofore overlooked mechanism is described for the removal of sediment in the vicinity of a structure, such as a bridge pier, located in erodible sediment and subjected to water flow. The strength of this mechanism depends on, among other things, the ratio of structure width to sediment grain size, b/D50. The mechanism results from the pressure gradient field imposed on the bed by the mean flow around the structure. The large pressure gradients created by the structure are confined to a relatively narrow region near the structure. The forces due to the pressure gradients acting on the sediment grains near the structure decrease with increasing values of b/D50. This mechanism helps explain the functional dependence of equilibrium local scour depth on b/D50 observed in both laboratory and field tests. It also explains why, in general, physical model local scour tests tend to overpredict prototype scour depths.
Overlooked Local Sediment Scour Mechanism
Transportation Research Record
Transportation Research Record: Journal of the Transportation Research Board ; 1890 , 1 ; 107-111
2004-01-01
Article (Journal)
Electronic Resource
English
PART 4 - HYDROLOGY, HYDRAULICS, AND WATER QUALITY - Overlooked Local Sediment Scour Mechanism
Online Contents | 2004
|Effect of Suspended Fine Sediment on Local Scour
HENRY – Federal Waterways Engineering and Research Institute (BAW) | 2002
|Sediment Scour at Piers with Complex Geometries
HENRY – Federal Waterways Engineering and Research Institute (BAW) | 2004
|Effect of sediment density in bridge pier scour experiments
DataCite | 2012
|Live-Bed Local Pier Scour Experiments
HENRY – Federal Waterways Engineering and Research Institute (BAW) | 2004
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