Home - Assessing Stream Channel Stability at Bridges in Physiographic Regions (FHWA-HRT-05-072) - Hydraulics - Engineering

Conferences
Software
Policy & Memos
Research
Publications
Training & Workshops
Staff
Links

Contents

Next >>

Assessing Stream Channel Stability at Bridges in Physiographic Regions
FHWA-HRT-05-072

PDF version (3.47 MB)

The objective of this study was to expand and improve a rapid channel stability assessment method developed previously by Johnson et al. to include additional factors, such as major physiographic units across the United States, a greater range of bank materials and complexities, critical bank heights, stream types and processes, sand bed streams, and in-channel bars or lack of bars. (1) Another goal of this study was to tailor Thorne's reconnaissance method for bridge inspection and stability assessment needs. (2) Stream-bridge intersections were observed across the United States to develop and test the stability assessment method. Site visits were conducted at 57 stream-bridge intersections in 14 physiographic regions and subregions. Data collected and included in the report include locations and global positioning system (GPS) coordinates of the bridges, the physiographic Province, land use, stream classification, bed and bar material, percent of sand in the bed material, controls in the banks or on the bed, bank vegetation, bank material, bank height, and any erosion-related characteristics. Variability in stream types and common characteristics within each of the physiographic regions also were described. Thirteen indicators were identified for the stability assessment method. For each indicator, a rating of poor, fair, good, or excellent was assigned. An overall rank was obtained by summing the 13 ratings. To address sensitivities of various stream types to the indicators and rankings, the appropriate ranges of rankings were determined for three categories of stream channels. Each of the 57 stream-bridge intersections also was described in terms of lateral and vertical stability. Finally, a simplified version of Thorne's stream reconnaissance field sheets is presented for collecting data for the stream stability assessment and to provide a record of conditions at each visit. (2)

Gary L. Henderson
Director, Office of Infrastructure
Research and Development

NOTICE

This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for its contents or use thereof. This report does not constitute a standard, specification, or regulation.

The U.S. Government does not endorse products or manufacturers. Trade and manufacturers' names appear in this report only because they are considered essential to the object of the document.

QUALITY ASSURANCE STATEMENT

The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement.

Technical Report Documentation Page
1. Report No. FHWA-HRT-05-072	2. Government Accession No.	3. Recipient's Catalog No.
4. Title and Subtitle Assessing Stream Channel Stability at bridges in Physiographic Regions		5. Report Date July 2006
		6. Performing Organization Code
7. Author(s) Peggy A. Johnson		8. Performing Organization Report No.
9. Performing Organization Name and Address Department of Civil and Environmental Engineering Pennsylvania State University University Park, PA 16802		10. Work Unit No. (TRAIS)
		11. Contract or Grant No. DTFH61-03-P-00353
12. Sponsoring Agency Name and Address Office of Infrastructure Research and Development Federal Highway Administration Turner-Fairbank Highway Research Center 6300 Georgetown Pike McLean, VA 22101		13. Type of Report and Period Covered Final Report, August 2003 to August 2004
		14. Sponsoring Agency Code
15. Supplementary Notes Contracting Officer's Technical Representative - J. Sterling Jones, HRDI-07; cosponsored by Jorge Pagan, Office of Bridge Technology
16. Abstract The objective of this study was to expand and improve a rapid channel stability assessment method developed previously by Johnson et al. to include additional factors, such as major physiographic units across the United States, a greater range of bank materials and complexities, critical bank heights, stream types and processes, sand bed streams, and in-channel bars or lack of bars. (1) Another goal of this study was to tailor Thorne's reconnaissance method for bridge inspection and stability assessment needs. (2) Stream-bridge intersections were observed across the United States to develop and test the stability assessment method. Site visits were conducted at 57 stream-bridge intersections in 14 physiographic regions and subregions. Data collected and included in the report include locations and global positioning system (GPS) coordinates of the bridges, the physiographic Province, land use, stream classification, bed and bar material, percent of sand in the bed material, controls in the banks or on the bed, bank vegetation, bank material, bank height, and any erosion-related characteristics. Variability in stream types and common characteristics within each of the physiographic regions also were described. Thirteen indicators were identified for the stability assessment method. For each indicator, a rating of poor, fair, good, or excellent was assigned. An overall rank was obtained by summing the 13 ratings. To address sensitivities of various stream types to the indicators and rankings, the appropriate ranges of rankings were determined for three categories of stream channels. Each of the 57 stream-bridge intersections also was described in terms of lateral and vertical stability. Finally, a simplified version of Thorne's stream reconnaissance field sheets is presented for collecting data for the stream stability assessment and to provide a record of conditions at each visit. (2)
17. Key Words Bridge scour, stream stability, inspection, bridge maintenance, hydraulics		18. Distribution Statement
19. Security Classification (of this report) Unclassified	20. Security Classification (of this page) Unclassified	21. No. of Pages 157	22. Price N/A