Scour Preventing Fairings for Bridges: Results from a Recent NCHRP-IDEA Project

A cost-effective optimized robust three-dimensional convex-concave hydrodynamic fairing with attached vortex generators was tested further for hydraulic structures such as bridge piers and abutments during a National Co-operative Highway Research Program - Innovations Deserving Exploratory Analysis (NCHRP-IDEA) project. Its shape prevents creation of scouring vortices that cause the local scour problem for any river level, speed, and angles of attack up to 20 degrees. This device exceeds requirements for HEC-23. Cost-effective versions are of stainless-steel or conventionally cast concrete that are attached to an existing or cast as part of the base of a new hydraulic structure above the footing, respectively. The vortex generators energize the decelerating near-wall flow with higher-momentum flow, resulting in a more steady, compact downstream separation and wake and substantially mitigated scour inducing vortical flow. While previously proven by computations and model-scale flume tests, new experimental test results from the NCHRP-IDEA project confirm that scAUR™ scouring-vortex-preventing fairings prevent foundation local scour for smaller sediments, wing-wall and spill-through abutments, and full-scale piers, as well as alleviating the effects of open-bed scour on foundations. Other advantages of this robust device 49 over other current approaches are: (1) much lower costs for scour prevention and bridge maintenance; (2) much lower probability of bridge failure;(3) lower river levels due to lower drag and lower flow blockage around the pier or abutment; (4) much lower possibility for debris and ice buildup; and (5) greater protection of piers and abutments against impact loads.

• Supplemental Notes:
  • This paper was sponsored by TRB committee AHD35 Bridge Management.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Simpson, Roger L
  • Byun, Gwibo
  • Mueller, Edmund C
• Conference:
  • Transportation Research Board 93rd Annual Meeting
  • Location: Washington DC
  • Date: 2014-1-12 to 2014-1-16
• Date: 2014

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; Photos; References;
• Pagination: 32p
• Monograph Title: TRB 93rd Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Bridge abutments; Bridge piers; Cost effectiveness; Fairings; Footings; Scour; Vortex shedding
• Identifier Terms: National Cooperative Highway Research Program
• Subject Areas: Bridges and other structures; Highways; Maintenance and Preservation; I60: Maintenance;

Filing Info

• Accession Number: 01519134
• Record Type: Publication
• Report/Paper Numbers: 14-4077
• Files: TRIS, TRB, ATRI
• Created Date: Mar 24 2014 12:01PM