LONG-TERM BEHAVIOR OF A PRESTRESSED CONCRETE I-GIRDER BRIDGE IN CHAMPAIGN COUNTY, ILLINOIS

This report describes the measured long-term behavior of a small prestressed concrete highway bridge. The three spans of about 46 ft (14.0 m) each were made with pretensioned I-section girders and a cast-in-place deck. Strains and camber were measured in the two instrumented girders for a period of 1067 days after transfer of prestress. The measured camber remained small, with values between 0.25 and 0.30 in. (6 to 8 mm) at the last reading. When corrected for the effects of initial temperature gradients, the camber is about 0.1 in (2.5 mm), while the predicted final camber is about 0.1f in. (3.5 mm). The concrete strains remained relatively small, since the girders in the bridge were not heavily prestressed. The measured strains were in relatively good agreement with strains computed using an analysis that took into account the measured creep and shrinkage properties of the girder and deck concretes. The same analysis indicates that the prestressing force after losses is somewhat lower than the designer assumed, largely as a result of not obtaining the desired initial forces in the prestressing bed. Creep and shrinkage specimens of both girder and deck concrete were stored outdoors in the same environment the bridge was subjected to and in a controlled environment laboratory. (FHWA)

  • Availability:
  • Supplemental Notes:
    • Prepared in cooperation with DOT, FHWA.
  • Corporate Authors:

    University of Illinois, Urbana-Champaign

    Department of Civil and Environmental Engineering
    205 North Mathews Avenue
    Urbana, IL  USA  61801-2352

    Illinois Department of Transportation

    Bureau of Materials and Physical Research
    126 East Ash Street
    Springfield, IL  USA  62704-4766
  • Authors:
    • Gamble, W L
  • Publication Date: 1979-12

Media Info

  • Pagination: n.p.

Subject/Index Terms

Filing Info

  • Accession Number: 00316418
  • Record Type: Publication
  • ISBN: UILU-ENG-79-2019
  • Report/Paper Numbers: FHWA/IL/UI/180 Intrm Rpt., FCP 40S1-122
  • Contract Numbers: IHR-93
  • Files: TRIS, STATEDOT
  • Created Date: Dec 30 1980 12:00AM