SHEAR FATIGUE TESTS OF PRESTRESSED CONCRETE I-BEAMS WITH WEB REINFORCEMENT

RESULTS ARE PRESENTED OF LABORATORY FATIGUE TESTS TO DETERMINE THE SHEAR STRENGTH OF PRESTRESSED CONCRETE BEAMS. SIX I-BEAMS WITH A FLANGE WIDTH OF 9 INCHES, DEPTH OF 18 INCHES, AND A FLANGE TO WEB RATIO OF 3 WERE TESTED. EACH BEAM WAS FIRST LOADED STATICALLY TO APPROXIMATELY 80 PERCENT OF ITS ULTIMATE FLEXURAL CAPACITY, AFTERWHICH IT WAS SUBJECTED TO REPEATED LOADS VARYING IN MAGNITUDE BETWEEN 20 AND 45 PERCENT OF ITS FLEXURAL CAPACITY FOR ABOUT 2,000,000 CYCLES. THE LOAD RANGE WAS THEN INCREASED AND CONTINUED UNTIL FAILURE OCCURRED. ONE BEAM FAILED IN SHEAR FATIGUE, ANOTHER BEAM FAILED IN FLEXURAL FATIGUE AFTER SHEAR FATIGUE DAMAGE HAD OCCURRED IN ONE SHEAR SPAN, AND THE OTHER FOUR BEAMS FAILED IN FLEXURAL FATIGUE. THE TESTS DEMONSTRATED THAT PRESTRESSED CONCRETE BEAMS HAVE A REMARKABLE SHEAR FATIGUE RESISTANCE. FURTHERMORE, SHEAR FATIGUE FAILURES DO NOT OCCUR SUDDENLY, BUT GIVE CONSIDERABLE WARNING AS INDICATED BY INCREASING DEFLECTION AND INCREASING CRACK WIDTH BEFORE FAILURE OCCURS. /BPR/

  • Supplemental Notes:
    • Hpr, 223
  • 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:
    • Hanson, J M
    • Hulsbos, C L
  • Publication Date: 1969-1

Subject/Index Terms

Filing Info

  • Accession Number: 00207907
  • Record Type: Publication
  • Source Agency: Bureau of Public Roads /US
  • Files: TRIS
  • Created Date: Jul 22 1994 12:00AM