Environmental Durability of Reinforced Concrete Deck Girders Strengthened for Shear with Surface-Bonded Carbon Fiber-Reinforced Polymer

Details

• Creators:
  Higgins, Christopher ; Dawson, Matthew R. ; Mitchell, Mikal M. ; Sopal, Gautam ; Senturk, A. Ekin
• Corporate Creators:
  Oregon State University. School of Civil and Construction Engineering
• Corporate Contributors:
  Oregon. Dept. of Transportation. Research Unit ; Oregon Transportation Research and Education Consortium
• Subject/TRT Terms:
  • Girders
  • Beams
  • Reinforced concrete
  • Floors
  • Plastics
  • Temperature endurance tests
  • Concrete bridges
  • Testing
  • Bridge decks Polymeric composites
• Publication/ Report Number:
  FHWA-OR-RD-09-17
• Resource Type:
  Tech Report
• Geographical Coverage:
  Oregon
• Edition:
  Final report.
• Corporate Publisher:
  Oregon. Dept. of Transportation
• Abstract:
  This research investigated the durability of carbon fiber-reinforced polymer composites (CFRP) used for shear strengthening reinforced ; concrete deck girders. Large beams were used to avoid accounting for size effects in the data analysis. The effort included determining ; the role of freeze-thaw, moisture, and fatigue on structural performance and developing analytical design procedures that account for ; durability. ; The results showed that moisture infiltration behind the CFRP, combined with freeze-thaw, was critical in reducing shear panel stiffness ; and shear capacity. Long-term moisture exposure alone produced only a minor decrease in shear capacity. Freeze-thaw, combined with ; fatigue, had little effect on shear capacity if water infiltration was minimized. Fatigue caused some debonding, but the debonding was ; not significant enough to affect capacity. ; Use of ACI-318 with ACI 440 provided conservative predicted shear strengths after environmental exposure. However, the ACI approach ; did not provide uniform levels of safety because the observed conservatism was built into the prediction for the unstrengthened base ; specimens but not for the CFRP contribution. Consequently, a recommendation of the research is to apply the environmental exposure ; factor at the final design step to limit the effective CFRP stress/strain. For locations with very large numbers of wet freeze-thaw cycles ; and extended exposure to continuous moisture, the environmental reduction factors should be reduced even further. To better predict the ; CFRP bond strength demands that can occur due to shear-moment interaction, a further check of the design should be made beyond those ; required by ACI-440.
  More +
• Format:
  PDF
• Funding:
  SPR 652
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/17195/dot_17195_DS1.pdf
• File Type:
  [PDF - 5.68 MB]
• Collection(s):
  University Transportation Centers
• Main Document Checksum:
  urn:sha-512:848683af59bcb370d1a7b2b24a5a791fbdac006f45fc31229cd519dd34c39b39ba7a0f33b64282f424edbc2d778a26b99d2abf8e7ea276fe046586ce4f0334d3