Steel Suspension Bridge Vulnerability and Countermeasures

The aim of this research is to: (1) increase the resistance of suspension bridges to an attack on any of their three major components: towers, main cables and suspenders; (2) extend the testing started in Pooled Fund Project 888, Validation of Numerical Modeling and Analysis of Steel Bridge Towers Subjected to Blast Loadings, to include older types of materials and connection details, and varying material conditions; and (3) develop high performance/lower intrusion countermeasure designs. The low intrusion is significant to bridge owners because the retrofit must not produce material degradation (e.g., corrosion), interfere with the operation of previously-installed mitigation measures for other hazards (e.g., seismic), or obstruct normal maintenance/inspection operations. Experimental and analytical work will verify and calibrate: (1) predictions of member behavior; (2) performance of current mitigation measures; and (3) performance of new design concepts and materials subjected to the loads outlined below. The test loads will replicate vehicle bombs or other standoff charges; hand-emplaced breaching charges, cutting charges, and mechanical cutting, as required. Explosive tests are to be conducted in a secure environment at a U.S. Army Corps of Engineers test facility. The study will include both small- and large-scale testing of steel suspension bridge elements, their connections, and, where practical, assembled groups of bridge elements. The response of early 20th century steel members to these loadings will be determined.Specimens for this portion will be obtained from bridges to be demolished: The Waldo-Hancock Bridge (Maine), the Crown Point Bridge (NY-Vt), and the Ft. Stueben Bridge (Ohio-WV). A limited on-site study, outlined in a prior Federal Highway Administration funding request, was conducted under Department of Homeland Security sponsorship, and will be continued under this study. The study of both retrofit designs and retrofit materials are within the scope. Retrofit methods include: external and internal tower reinforcement and energy routing; main cable wrapping; suspender replacement materials; and energy-absorbing suspender sockets. Design issues to be considered include the typically severe size and weight limitations found on existing structures, as well as the need to address practical construction- and maintenance-imposed restrictions. The performance of advanced materials will be specifically assessed. This includes material combinations beyond those considered under Pooled Fund Project 888.

• Record URL:
  http://www.pooledfund.org/Details/Study/444

Language

• English

Project

• Status: Completed
• Funding: $1974697
• Contract Numbers:

  TPF-5(216)

• Sponsor Organizations:

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590

  U.S. Department of Homeland Security

  Washington, DC  United States 

  Golden Gate Bridge, Highway and Transportation District

  BOX 9000, PRESIDIO STATION
  SAN FRANCISCO, CA  United States  94129
• Project Managers:

  Duwadi, Sheila

• Start Date: 20211223
• Expected Completion Date: 0
• Actual Completion Date: 20211223
• Source Data: RiP Project 33913

Subject/Index Terms

• TRT Terms: Blast loads; Bridge design; Cable stayed bridges; Calibration; Countermeasures; Retrofitting; Risk analysis; Steel bridges; Suspension bridges; Terrorism
• Subject Areas: Bridges and other structures; Construction; Design; Highways; Security and Emergencies;

Filing Info

• Accession Number: 01479093
• Record Type: Research project
• Source Agency: Federal Highway Administration
• Contract Numbers: TPF-5(216)
• Files: RIP, USDOT
• Created Date: Apr 23 2013 1:00AM