CONCRETE STRAINS IN PRE-TENSIONED CONCRETE STRUCTURAL MEMBERS - PRELIMINARY REPORT

THE PRELIMINARY RESULTS, AT THE END OF ONE YEAR, ARE PRESENTED OF A LONG-TERM STUDY OF THE CONCRETE STRAINS IN PRE-TENSIONED CONCRETE STRUCTURAL MEMBERS. THIS STUDY IS PART OF A COMPREHENSIVE INVESTIGATION, AIMED AT THE DEVELOPMENT OF A RATIONAL BASIS FOR THE PREDICTION OF PRESTRESS LOSSES IN SUCH MEMBERS. RECTANGULAR PRE-TENSIONED CONCRETE SPECIMENS WERE FABRICATED AT TWO SELECTED PRESTRESSED CONCRETE PLANTS IN PENNSYLVANIA, AND STORED IN A MODERATE ENVIRONMENT. SIX LEVELS OF AVERAGE INITIAL CONCRETE STRESS AND FIVE STRESS GRADIENTS WERE REPRESENTED BY THESE SPECIMENS. STRAIN MEASUREMENTS INDICATE THAT THE ELASTIC AND CREEP STRAINS ARE BOTH PROPORTIONAL TO THE RATIO OF INITIAL CONCRETE STRESS TO CONCRETE STRENGTH, AND THAT THE SHRINKAGE STRAIN IS STRONGLY AFFECTED BY THE AMOUNT OF LONGITUDINAL STEEL IN THE MEMBER. IT IS ALSO FOUND THAT FOR THE DURATION REPORTED HEREIN, THE EFFECT OF STRESS GRADIENT ON THE CREEP STRAIN IS INSIGNIFICANT, THE SHRINKAGE STRAIN VARIES DIRECTLY WITH THE LOGARITHM OF TIME, AND THE CREEP STRAIN VARIES WITH THE SQUARE OF THE LOGARITHM OF TIME. /AUTHOR/

  • Supplemental Notes:
    • Hpr, 66-17
  • Corporate Authors:

    Lehigh University

    Bethlehem, PA  United States  18015

    Pennsylvania Department of Highways

    400 North Street
    Harrisburg, PA  United States  17120-0095

    Bureau of Public Roads /US

    400 7th Street, SW
    Washington, DC  United States  20590
  • Authors:
    • Huang, T
    • FREDERICKSON, D C
  • Publication Date: 1969-7

Subject/Index Terms

Filing Info

  • Accession Number: 00212066
  • Record Type: Publication
  • Source Agency: Bureau of Public Roads /US
  • Files: TRIS
  • Created Date: Jan 5 1970 12:00AM