Repairing/strengthening of bridges with post-tensioned FRP materials and performance evaluation.

Details

• Creators:
  Cai, C.S. ; Xia, Miao
• Corporate Creators:
  Louisiana State University. Dept. of Civil and Environmental Engineering
• Corporate Contributors:
  United States. Federal Highway Administration ; Louisiana. Dept. of Transportation and Development
• Subject/TRT Terms:
  • Bridges
  • Rehabilitation (Maintenance)
  • Fiber composites
  • Fiber reinforced polymers
  • Posttensioning
  • Girders
  • Flexural strength
  • Mechanical properties
  • Finite element method
• Publication/ Report Number:
  FHWA/LA.11/488
• Resource Type:
  Tech Report
• Geographical Coverage:
  Louisiana
• Corporate Publisher:
  Louisiana Transportation Research Center
• Abstract:
  One of the challenges that transportation agencies are facing is to keep bridges in good condition during their service life. ; Numerous bridges are classified as structurally and/or functionally deficient in the country. In the state of Louisiana, 4,591 ; bridges, or 34 percent of the total 13,426 bridges, are classified as substandard. Load capacity degradation, increased gross ; vehicle weight, and increasing traffic demand lead to the deficiencies. One of the most effective ways to solve the problem ; is to use composite materials to strengthen existing bridges. As rapidly developed over the past several decades, different ; kinds of composite fiber reinforced polymers (FRP) have been regarded as one of the best solutions to several problems ; associated with transportation and civil engineering infrastructures. Some of the major benefits of FRP include high strength ; to weight ratio, high fatigue endurance, excellent corrosion resistance, low thermal expansion, and the ease of fabrication, ; manufacturing, handling, and installation. The main objective of this research was to develop a flexural resistance designing ; process using post-tensioning prestressed carbon reinforced polymers (CFRP) laminates adhering to bridge girders to avoid ; various possible flexural failure modes. It is noted that, in the original plan, a steel bridge and a concrete bridge was to be ; rehabilitated with prestressed FRP laminates or rods and the bridge performance was to be monitored. However, the sponsor ; decided not to pursue the field implementation due to cost. This report presents a review of the up-to-date work on bridges ; strengthened with FRP materials. Mechanical properties of FRP fibers and composites were presented in detail. ; Investigators presented previous research findings on experiments of FRP composite materials used as various prestressed ; tendons, and the analyses for different failure modes were introduced. To investigate the effect of rehabilitation with ; prestressed CFRP laminates, two 3-D finite element analyses were conducted to examine the deflection and bottom fiber ; stress at the mid-span. A detailed designing process of rehabilitation with prestressed CFRP laminates was presented in this ; report. A feasible plan to enhance the flexural capability of an existing bridge with externally prestressed CFRP laminates ; according to AASHTO and ACI code specifications was also proposed in this report
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• Format:
  PDF
• Funding:
  LTRC Project Number: 07-3ST ; SIO: 30000130
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/29399/dot_29399_DS1.pdf
• File Type:
  [PDF - 1.48 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:6ddedcff274f532f2cfc99d787ead69b9463d1822290ae761a29103549350d0a