Use of Advanced Materials to Enhance the Lateral Stability of Prestressed Concrete Girders

Precast pretensioned concrete girders offer low initial cost, low life cycle costs and excellent durability. Consequently, they are the most widely used girder type in the country for new bridges. When they were first introduced in the 1950s, the AASHTO Bridge Committee considered a provision to limit their span to a maximum of 60 ft. Today, the longest span that has been used is over 220 ft. This demonstrates the inexorable rise in span lengths over the years, driven by a combination of urban congestion and environmental limitations, which often prevents the placement of an intermediate column at the location best suited to the structural requirements. Girder cross-sections have changed in response to the demand for longer spans. Typically, the depth has become greater, and the elements, thinner. While these changes benefit the in-service behavior, they simultaneously jeopardize lateral stability during handling. For girders shorter than about 125 ft, stability seldom poses a problem, but its influence increases with span length. The potential for instability is greatest during handling, because then the girder is free to undergo rigid body rotations, referred to herein as “roll”, about its “roll axis”, namely the line joining the two lifting points. The roll rotation causes a component of the girder weight to act in the weak direction, i.e. along the x-axis, with moments about the y-y axis. The resulting lateral deflection means that the girder weight is no longer directly below the roll axis, thereby causing further roll. A need thus exists for longer girders, but the design requirements for them appear to be mutually exclusive; high strength and stiffness with respect to vertical loads (for in-service behavior), and good lateral and torsional resistance (to promote lateral stability), but low weight (for hauling). Ultra high performance concrete (UHPC) is a candidate material, but the cross-section shapes that have so far been proposed (for example in PCI-sponsored research) appear to have focused on the in-service condition and to have disregarded stability.

• Record URL:
  https://abc-utc.fiu.edu/research-projects/use-of-advanced-materials-to-enhance-the-lateral-stability-of-prestressed-concrete-girders/

Language

• English

Project

• Status: Active
• Funding: $75000
• Contract Numbers:

  69A3551747121

• Sponsor Organizations:

  Accelerated Bridge Construction University Transportation Center (ABC-UTC)

  Florida International University
  10555 W. Flagler Street
  Miami, FL  United States  33174

  Office of the Assistant Secretary for Research and Technology

  University Transportation Centers Program
  Department of Transportation
  Washington, DC  United States  20590
• Performing Organizations:

  University of Washington, Seattle

  Civil and Environmental Engineering Department
  201 More Hall, Box 352700
  Seattle, WA  United States  98195-2700
• Principal Investigators:

  Stanton, John

• Start Date: 20230916
• Expected Completion Date: 0
• Actual Completion Date: 0
• USDOT Program: University Transportation Centers

Subject/Index Terms

• TRT Terms: Bridge design; Girders; Prestressed concrete; Ultra high performance concrete
• Subject Areas: Bridges and other structures; Construction; Design; Highways; Materials;

Filing Info

• Accession Number: 01889317
• Record Type: Research project
• Source Agency: Accelerated Bridge Construction University Transportation Center (ABC-UTC)
• Contract Numbers: 69A3551747121
• Files: UTC, RIP
• Created Date: Jul 31 2023 12:27AM