Trends in live-bed pier scour at selected bridges in South Carolina

Andral W. Caldwell; Stephen T. Benedict

doi:10.1061/41147(392)8

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Trends in live-bed pier scour at selected bridges in South Carolina

Andral W. Caldwell·Stephen T. Benedict

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Abstract

The U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, used ground-penetrating radar to collect measurements of live-bed pier scour at 78 bridges in the Piedmont and Coastal Plain physiographic provinces of South Carolina. The 141 measurements of live-bed pier-scour depth ranged from 0.5 to 5.1 meters. Using hydraulic data estimated with a one-dimensional flow model, predicted live-bed scour depths were computed with scour equations from the Hydraulic Engineering Circular 18 and compared with measured scour. This comparison indicated that predicted pier-scour depths generally exceeded the measured pier-scour depths. At times, predicted pier-scour depths were excessive with overpredictions as large as 7.0 meters. Relations in the live-bed pier-scour data also were investigated, leading to the development of an envelope curve for assessing the upper-bound of live-bed pier scour using pier width as the primary explanatory variable. The envelope curve developed with the field data has limitations, but it can be used as a supplementary tool for assessing the potential for live-bed pier scour in South Carolina. This paper will present findings related to the field investigation of live-bed pier scour. A companion paper presents findings related to live-bed contraction scour that was studied during the same field investigation.

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Source-reported bounding extent: 32.0346° to 35.215402° latitude; -83.353238° to -78.541087° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Andral W. Caldwell, Stephen T. Benedict. 2012-04-26. Trends in live-bed pier scour at selected bridges in South Carolina. https://doi.org/10.1061/41147(392)8

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