ESTIMATION OF CONCRETE STRAINS AND PRESTRESS LOSSES IN PRETENSIONED MEMBERS

THIS REPORT DESCRIBES A LONG-TERM STUDY OF CONCRETE STRAINS IN PRETENSIONED CONCRETE STRUCTURAL MEMBERS. TEST DATA OVER A PERIOD OF THREE YEARS HAVE BEEN INCLUDED IN THIS STUDY. THE CONCRETE STRAINS ARE SEPARATED INTO THREE COMPONENTS: ELASTIC SHORTENING, SHRINKAGE AND CREEP AND A FUNCTIONAL EXPRESSION IS DEVELOPED FOR EACH. COMBINING THESE COMPONENTS, A GENERAL STRESS-STRAIN-TIME RELATIONSHIP OF CONCRETE IS DERVIED WHICH ALLOWS THE ESTIMATION OF THE CONCRETE STRAIN WHEN THE OTHER TWO VARIABLES ARE GIVEN. THE CONCRETE STRESS-STRAIN-TIME RELATIONSHIP IS FURTHER COMBINED WITH A SIMILAR RELATIONSHIP FOR THE PRESTRESSING STRANDS, AND A GENERAL ANALYTICAL PROCEDURE FOR THE PREDICTION OF PRESTRESS LOSS IS DEVELOPED. APPLICATION OF THIS GENERAL PROCEDURE TO UNIFORMLY (CENTRALLY) PRESTRESSED CONCRETE MEMBERS IS DEMONSTRATED, AND RESULTS COMPARED WITH THE EXPERIMENTALLY OBTAINED VALUES. PENDING FURTHER FERIFICATIONS, THIS SAME PROCEDURE, WITH MINOR MODIFICATIONS, IS EXPECTED TO BE ALSO APPLICABLE TO MEMBERS PRESTRESSED NON-UNIFORMLY (ECCENTRICITY) AND/OR SUBJECTED TO EXTERNAL LOADING. /AUTHOR/

  • Supplemental Notes:
    • Rept No 339.7 1 APP
  • Corporate Authors:

    Lehigh University

    Bethlehem, PA  United States  18015
  • Authors:
    • Ying, H T
    • Schultchen, E G
    • Huang, T
  • Publication Date: 1972-5

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 45 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00210051
  • Record Type: Publication
  • Report/Paper Numbers: Res Rept
  • Files: TRIS
  • Created Date: Jun 5 1974 12:00AM