EFFECT OF LOAD VARIATIONS ON THE FLEXURAL FATIGUE STRENGTH OF PLAIN CONCRETE

THE RESULTS OF A LABORATORY STUDY ARE REPORTED ON THE FATIGUE CHARACTERISTICS OF PLAIN CONCRETE. THE PRIMARY GOAL WAS TO EVALUATE THE EFFECT OF LOAD VARIATIONS ON THE FATIGUE LIFE TO DETERMINE WHEATHER THE MINER HYPOTHESIS ADEQUATELY REPRESNTS CUMULATIVE DAMAGE. TO OBTAIN THE NECESSARY DATA, 6X6X64-IN. PLAIN CONCRETE BEAMS WERE SUBJECTED TO TWO LEVELS OF REPETITIVE FLEXURAL LOADS UNTIL FAILURE OCCURED. THE MAGNITUDE AND DIRECTION OF THE CHANGE AND THE NUMBER OF CYCLES APPLIED AT THE FIRST STRESS LEVEL WERE VARIED. TEST RESULTS WERE EVALUATED IN COMPARISON WITH THE DATA FROM MONOTONIC FATIGUE TESTS, WHICH WERE USED TO ESTABLISH THE BASIC S/N RELATIONSHIP FOR THIS STUDY. A STATE-OF-THE-ART DISCUSSION COVERS PREVIOUS RESEARCH ON THE FATIGUE CHARACTERISTICS OF PLAIN CONCRETE. BASED ON THE RESULTS, IT IS CONCLUDED THAT THE MINER HYPOTHESIS REFLECTS THE CUMULATIVE DAMAGE EFFECTS FROM VARIATIONS IN THE FATIGUE LOADING IN A REASONABLE MANNER. THIS IMPLIES THAT DAMAGE OCCURS LINEARLY WITH REPETITIONS OF LOAD, AND IS PROPORTIONAL TO THE LEVEL OF STRESS. DATA FROM FATIGUE TESTS ARE QUITE SCATTERED; THEREFORE, CAUTION SHOULD BE EXERCISED IN USING THE S/N RELATIONSHIP FOR STRUCTURAL DESIGN. /FHWA/

  • Availability:
  • Corporate Authors:

    Federal Highway Administration

    Office of Research, Structures and Applied Mechanics Division, 1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Ballinger, C A
  • Publication Date: 1972-9

Media Info

  • Pagination: 71 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00212124
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • ISBN: 2622022
  • Report/Paper Numbers: FHWA-RD-72- 2 Final Rpt.
  • Files: TRIS, USDOT
  • Created Date: Apr 17 1976 12:00AM