CREEP AND SHRINKAGE OF CONCRETE IN OUTDOOR EXPOSURE AND RELAXATION OF PRESTRESSING STEEL

A STUDY OF THE LONG-TIME BEHAVIOR OF PRESTRESSED CONCRETE BEAMS REQUIRES THE DETERMINATION OF STRESS LOSSES CAUSED BY CREEP AND SHRINKAGE OF CONCRETE AND BY RELAXATION OF PRESTRESSING STEEL. LOSSES CAN BE CALCULATED ACCURATELY ONLY IF CREEP, SKRINKAGE AND RELAXATION ARE DETERMINED FOR THE MATERIALS ACTUALLY USED IN THE BEAMS. FURTHERMORE, IF THE CREEP AND SHRINKAGE CHARACTERISTICS OF CONCRETE ARE DETERMINED BY TESTS, THE ENVIRONMENTAL CONDITIONS IN SUCH TESTS MUST APPROXIMATE THOSE TO WHICH THE PRESTRESSED BEAMS ARE EXPOSED. OUTDOOR CREEP AND SHRINKAGE TESTS OF 24 CONCRETE CYLINDERS, AND INDOOR RELAXATION TESTS OF 20 SAMPLES OF PRESTRESSING WIRE AND STRAND OBTAINED WITH THE SAME BASIC MODEL EXPRESSES SHRINKAGE STRAIN, CREEP STRAIN OR RELAXATION LOSS AS A FUNCTION OF TIME. NUMBERICAL COEFFICIENTS IN THE EQUATIONS ARE EVALUATED BY MULTIPLE REGRESSION ANALYSES. THE RESULTS OF THE TESTS ARE USED IN COMPUTATIONS OF LONG-TIME STRAINS IN SIX PRESTRESSED CONCRETE BRIDGE BEAMS. THE COMPUTED STRAINS COMPARE FAVORABLY WITH THE RESULTS OF STRAIN MEASUREMENTS ON THE BEAMS. /AUTHOR/

• Record URL:
  • http://onlinepubs.trb.org/Onlinepubs/sr/sr66/66-006.pdf
• Supplemental Notes:
  • pp 103-131, 19 FIG, 9 TAB, 3 PHOT, 11 REF, 2 APP Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
• Corporate Authors:

  Highway Research Board

  Washington, DC   
• Authors:
  • Kingham, R I
  • Fisher, J W
  • Viest, I M
• Conference:
  • 40th Annual Meeting of the Highway Research Board
  • Location: Washington DC, United States
  • Date: 1961-1-9 to 1961-1-13
• Publication Date: 1961

Media Info

• Monograph Title: AASHO road test; technical staff papers
• Serial:
  • Highway Research Board Special Report
  • Issue Number: 66
  • Publisher: Highway Research Board

Subject/Index Terms

• TRT Terms: Alternatives analysis; Beams; Bridge construction; Bridge foundations; Bridges; Calculation; Concrete; Concrete tests; Construction; Creep; Prestressed concrete; Prestressing; Regression analysis; Shrinkage; Steel; Strain (Mechanics); Strain measurement
• Uncontrolled Terms: Computation
• Old TRIS Terms: Concrete creep; Strains
• Subject Areas: Bridges and other structures; Construction; Data and Information Technology; Highways;

Filing Info

• Accession Number: 00209067
• Record Type: Publication
• Files: TRIS, TRB
• Created Date: Sep 29 1994 12:00AM