TIME DEPENDENT BEHAVIOR OF NONCOMPOSITE AND COMPOSITE PRESTRESSED CONCRETE STRUCTURES UNDER FIELD AND LABORATORY CONDITIONS

COMPUTER ANALYSIS METHODS, BASED ON RATE OF CREEP AND SUPERPOSITION METHODS, FOR PREDICTING TIME DEPENDENT DEFORMATIONS IN PRESTRESSED CONCRETE GIRDERS, ARE PRESENTED. THE EFFECTS OF ARBITRARY VARIATIONS OF CREEP AND SHRINKAGE IN NONCOMPOSITE BEAMS, AND OF DIFFERENTIAL CREEP AND SHRINKAGE IN SIMPLY-SUPPORTED AND CONTINUOUS-COMPOSITE GIRDERS, UNDER DIFFERENT CURING AND ENVIRONMENTAL CONDITIONS, CAN BE TAKEN INTO ACCOUNT. A SIMPLE, SINGLE STEP PROCEDURE, BASED ON THE SUPERPOSITION METHOD, FOR CALCULATING LOSS OF PRESTRESS, CHANGES IN CAMBER, AND REDISTRIBUTION OF STRESSES AND STRAINS IN NONCOMPOSITE AND COMPOSITE PRESTRESSED STRUCTURES WAS ALSO DEVELOPED. PREDICTED DEFORMATIONS ARE COMPARED WITH MEASUREMENTS MADE OVER A PERIOD OF 2 YEARS ON A FULL-SIZE, 3-SPAN PRESTRESSED I-BEAM HIGHWAY BRIDGE STRUCTURE, AND WITH THE BEHAVIOR OF A 1/8-SCALE MODEL BEAM STRUCTURE CONSISTING OF A SINGLE ROW OF PRESTRESSED I-BEAMS AND CAST-IN-PLACE DECK CONCRETE CONTINUOUS OVER THREE SPANS WHICH WAS STUDIED FOR A PERIOD OF 270 DAYS. EFFECTS OF THE SIZE AND SHAPE OF CREEP AND SHRINKAGE SPECIMENS WERE STUDIED, AND IT WAS FOUND THAT THE NORMAL TRENDS OF DECREASING CREEP AND SHRINKAGE WITH INCREASING MEMBER SIZE CANNOT BE INDISCRIMINATELY EXTRAPOLATED TO EITHER VARIABLE ENVIRONMENTAL CONDITIONS OR TO VERY SMALL SPECIMENS. IT WAS ALSO SHOWN THAT UNDER HIGHLY VARIABLE ENVIRONMENTAL CONDITIONS, CREEP STRAINS MUCH LARGER THAN THOSE NORMALLY ASSOCIATED WITH THE AVERAGE RELATIVE HUMIDITY MAY OCCUR WHILE THE SHRINKAGE STRAINS DEVELOP ONLY TO THE EXPECTED VALUES. /FHWA/

  • Supplemental Notes:
    • IHR-93
  • Corporate Authors:

    University of Illinois, Urbana-Champaign

    Urbana, IL  USA  61801

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  USA  20590
  • Authors:
    • Mossiossian, V
    • Gamble, W L
  • Publication Date: 1971-11

Media Info

  • Pagination: 535 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00208051
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • Files: TRIS, USDOT
  • Created Date: Jun 28 1972 12:00AM