A STATISTICAL STUDY OF THE STATIC AND FATIGUE PROPERTIES OF HIGH STRENGTH PRESTRESSING STRAND

AN INVESTIGATION HAS BEEN MADE OF THE STATIC AND FATIGUE PROPERTIES OF 1/2-IN. 270 KSI 7-WIRE PRESTRESSING STRAND. THE SPECIFIC PROPERTIES INVESTIGATED WERE THE STRESS-STRAIN RELATIONSHIP UP TO ULTIMATE LOAD, FATIGUE LIFE UNDER LABORATORY CONDITIONS, AND THE EFFECT OF LOW TEMPERATURE ON THE FATIGUE LIFE. SAMPLES OF STRAND FROM FIVE DIFFERENT MANUFACTURERS WERE USED TO ESTABLISH THE STRESS-STRAIN RELATIONSHIPS. THE RESULTS INDICATE THAT ALL SAMPLES MEET THE MINIMUM REQUIREMENTS SPECIFIED IN ASTM A416-64. THE S-N RELATIONSHIPS WERE DEVELOPED FOR STRAND FROM THREE OF THE MANUFACTURERS. IN EACH CASE, TWO DIFFERENT MINIMUM STRESS LEVELS /40% AND 60% OF THE MINIMUM SPECIFIED ULTIMATE STRENGTH/ WERE USED. A STATISTICAL ANALYSIS WAS MADE OF THE DATA, AND EQUATIONS ARE DEVELOPED WHICH EXPRESS THE FATIGUE LIFE AS A FUNCTION OF THE MINIMUM AND MAXIMUM STRESS LEVELS. THE RESULTING S-N RELATIONSHIPS ARE COMPARED WITH THOSE DEVELOPED IN EARLIER WORK FOR 7/16-IN. 250 KSI 7-WIRE STRAND. FINALLY, A PILOT STUDY WAS MADE OF THE EFFECT OF LOW TEMPERATURE /O DEGREES F/ ON THE FATIGUE LIFE OF THE 1/2-IN. 270 KSI STRAND. SAMPLES FROM ALL FIVE MANUFACTURERS WERE INCLUDED IN THIS PART OF THE INVESTIGATION. THE SPECIMENS TESTED AT LOW TEMPERATURE WERE COMPARED WITH A GROUP TESTED AT NORMAL LABORATORY TEMPERATURE. ONE STRESS RANGE WAS USED IN ALL TESTS. THE RESULTS INDICATE THAT THIS DECREASE IN TEMPERATURE APPARENTLY HAS LITTLE EFFECT ON THE FATIGUE LIFE OF THE STRAND. /AUTHOR/

• Supplemental Notes:
  • Hpr-1/23/, STATE NO 365
• Corporate Authors:

  Lehigh University

  Bethlehem, PA  United States  18015
• Authors:
  • Tide, RHR
  • VanHorn, D A
• Publication Date: 1966-6

Subject/Index Terms

• TRT Terms: Deformation curve; Fatigue (Mechanics); Fatigue tests; Laboratory tests; Low temperature; Prestressed concrete; Prestressing; Static tests; Statistical analysis
• Uncontrolled Terms: Fatigue life; Prestressing strand
• Subject Areas: Bridges and other structures; Data and Information Technology; Highways;

Filing Info

• Accession Number: 00207795
• Record Type: Publication
• Source Agency: Bureau of Public Roads /US
• Files: TRIS
• Created Date: Aug 1 1994 12:00AM