BOND OF EPOXY COATED PRESTRESSING STRAND. FINAL REPORT

The effect of the epoxy coating on transfer length and development length properties of three diameters of prestressing strand was investigated. The epoxy coated prestressing strand was seven-wire strand coated with an epoxy and impregnated with a crushed glass grit. Approximately sixty specimens were cast to determine the transfer length and development length of both epoxy coated and bare prestressing strand. The transfer length was determined by measuring concrete strains before and after release. Development lengths were determined through a series of flexural tests. A cyclic loading was applied to twelve specimens to determine the effect of fatigue on bond of epoxy coated strand. Analytical expressions were developed for estimating transfer length and development length. The transfer length model was based on plastic and elastic zones of bond stress within the transfer length. The development length model was based on the transfer length model plus a plastic bond stress relationship throughout the flexural bond length. The experimental and analytical results from this research were compared to the results in the literature and previously proposed bond provisions.

• Corporate Authors:

  North Carolina State University, Raleigh

  Center for Transportation Engineering Studies, P.O. Box 7908
  Raleigh, NC  United States  27695

  North Carolina Department of Transportation

  P.O. Box 25201, 1 South Wilmington Street
  Raleigh, NC  United States  27611

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Cousins, T E
  • Johnston, D W
  • Zia, P
• Publication Date: 1986-12

Media Info

• Features: Appendices; Figures; References; Tables;
• Pagination: 191 p.

Subject/Index Terms

• TRT Terms: Bonds; Coatings; Epoxides; Estimating; Fatigue (Mechanics); Flexural strength; Mathematical models; Prestressed concrete; Prestressing; Repeated loads; Strain (Mechanics); Time duration; Transfers
• Uncontrolled Terms: Development length; Prestressing strands; Transfer length
• Old TRIS Terms: Epoxy; Flexural bond; Strains
• Subject Areas: Finance; Highways; Materials; I32: Concrete;

Filing Info

• Accession Number: 00464613
• Record Type: Publication
• Report/Paper Numbers: FHWA/NC/87-005
• Contract Numbers: ITRE 23241-85-3
• Files: TRIS, USDOT, STATEDOT
• Created Date: Dec 31 1988 12:00AM