Low Vertical Clearance Truss Bridges : Risk Assessment and Retrofit Mitigation Study

Details

• Creators:
  Swett, Geoffrey D. ; Bedi, Gary
• Corporate Creators:
  Washington (State). Dept. of Transportation. Bridge and Structures Office
• Corporate Contributors:
  United States. Federal Highway Administration
• Subject/TRT Terms:
  • Truss bridges
  • Steel bridges
  • Steel Trusses
  • Vertical Clearance
  • Portals
  • Sways
  • Vehicle Over Height Impact
• Publication/ Report Number:
  WA-RD 876.1
• Resource Type:
  Tech Report
• Geographical Coverage:
  Washington;United States
• Corporate Publisher:
  Washington (State). Dept. of Transportation
• Abstract:
  The Washington State Department of Transportation (WSDOT) has over 60 steel truss bridges in its inventory with vertical clearances less than the minimum 16’-6” required for new bridges. This study evaluates the risks of oversized vehicle impacts to existing truss bridges with low vertical clearances. The Skagit River Bridge SR5/712 was hit by an oversized load on May 23rd, 2013 resulting in a catastrophic collapse. At the time of the collapse, the Skagit River Bridge had less than the minimum vertical clearance. WSDOT undertook this study to evaluate the risks of a similar occurrence happening and to evaluate potential mitigation schemes. Scoping level construction estimates for each scheme were then developed for all structures with substandard vertical clearance. All bridges were prioritized based on risk using a range of evaluation criteria. The goal and eventual purpose of the study is to be used as an asset management tool for programming future retrofit projects and for procuring the necessary funding.
• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/34547/dot_34547_DS1.pdf
• File Type:
  [PDF - 78.55 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:c39108ded7e0ba9e6f0c31fec2b70a5a7430aa767b76c1bc5d60448510014095