APPRAISAL OF TECHNIQUES TO REDUCE EMBEDMENT FRICTION WHILE POST-STRESSING CONCRETE

In this report, two concepts for reducing friction losses along post-tensioned tendons in pavement slabs are studied. One concept involved the use of vibration techniques to increase stressing efficiency, and the other concept included the reduction of friction coefficient through the use of a material which would also act as a grout after stressing the tendon. For the vibration techniques, three vibration systems were constructed and tested. One was based on the use of hydraulic pressure pulsations to cause a sharp jerking action on a tendon. The desired effect was not accomplished with the system constructed. The other two systems used impact generated vibrations, which affected normal forces along the tendons. The impact vibrations did produce changes in the friction losses but not that which would be desirable for post-tensioned tendons in long pavement slabs. Grout materials tested were two, 2-part and two heat cure epoxy resins. Tendon heating through the use of an AC arc welder was also investigated in order to determine the feasibility of this method for setting the heat cure epoxies. The results of these tests were inconclusive but do show promise for future investigations. /FHWA/

  • Supplemental Notes:
    • Sponsored by the Department of Transportation, Federal Highway Administration.
  • Corporate Authors:

    Tetradyne Corporation

    1681 South Broadway
    Carrollton, TX  United States  75006
  • Authors:
    • Chandler, R W
    • Brownlow, R K
    • Johnson, D
  • Publication Date: 1978-3-10

Media Info

  • Pagination: 88 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00188524
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • Report/Paper Numbers: FHWA-RD-78- 45 Final Rpt., FCP 35E3-032
  • Contract Numbers: DOT-FH-11-8894
  • Files: TRIS, USDOT
  • Created Date: Mar 14 1979 12:00AM