Investigation of Carbon Fiber Composite Cables (CFCC) in Prestressed Concrete Piles

The Florida Department of Transportation (FDOT) commonly uses prestressed concrete piles in bridge foundations. These piles are prestressed with steel strands that, when installed in aggressive or marine environments, are subject to corrosion and therefore rapid degradation. Many solutions may address this issue, but they are not long-term. Hence, it would be desirable to use advanced materials that do not corrode. The goal of this research was to assess the suitability of using carbon fiber composite cables (CFCC), which do not corrode, in lieu of conventional steel prestressing strands. Five 24-in. square prestressed concrete piles, three 40-ft long and two 100-ft long, were cast using 0.6-in. diameter CFCC strands produced by Tokyo Rope Manufacturing Company. A special anchoring system was used because CFCC strands cannot be conventionally gripped using wedges and a jack. The techniques employed to prestress these strands were documented, as well as the unique aspects involved in constructing and precasting CFCC-prestressed piles. During strand detensioning, stresses were monitored in the concrete at the piles' ends to determine the transfer length of CFCC strands, as a means of evaluating their bond characteristics. Development length tests and flexural tests were performed on two of the 40-ft piles at the FDOT Marcus H. Ansley Structures Research Center to further assess the performance of the CFCC strands. Lastly, the two 100-ft piles were driven at a bridge construction site, adjacent to standard steel-prestressed concrete piles. During driving operations, the behavior of the piles was monitored using embedded data collectors and a Pile Driving Analyzer®. The precasting efforts and test results show that the performance of piles prestressed with CFCC strands is comparable to those prestressed with steel. Using CFCC strands in prestressed concrete piles for bridge foundations, particularly in harsh environments, could potentially result in bridges that require less maintenance and have longer lifespans.

Language

  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 307p

Subject/Index Terms

Filing Info

  • Accession Number: 01526318
  • Record Type: Publication
  • Report/Paper Numbers: 031045
  • Contract Numbers: BDK83-977-17
  • Files: TRIS, ATRI, STATEDOT
  • Created Date: May 12 2014 11:37AM