FATIGUE BEHAVIOR OF STRUCTURAL STEELS AND THEIR WELDMENTS

THE RELIABILITY OF THE RECENTLY INTRODUCED HIGH-STRENGTH STEELS AND THEIR WELDMENTS IN CONNECTION WITH REPEATED LOAD APPLICATIONS WERE INVESTIGATED. STEELS CONSIDERED WERE A7, A36, A373, A242, A441, V50, V60, SSS, AND T1-A. THE VARIOUS STRUCTURAL STEELS AND THEIR WELDMENTS WERE EVALUATED FROM TWO VIEWPOINTS, FIRST, THE FATIGUE PROPERTIES OF THE MATERIALS IN QUESTION WERE COMPARED TO ESTABLISH STANDARD MINIMUM REQUIREMENTS, AND SECOND, THE FATIGUE PROPERTIES OF THE NEWLY INTRODUCED MATERIALS WERE COMPARED TO THE FATIGUE PROPERTIES OF THE STEEL KNOWN, USED AND PROVEN THROUGH A LONG PERIOD OF TIME. ALSO, THE PROPERTIES OF THE WELD METAL AND OF THE TRANSITION ZONE WERE COMPARED TO THE PROPERTIES OF THE BASE METALS. THE FATIGUE PROPERTIES OF VARIOUS GRADES OF STRUCTURAL STEEL AND THEIR WELDMENTS WERE EXAMINED IN COMPARISON WITH THE AMERICAN WELDING SOCIETY SPECIFICATIONS AND STRESSES RECOMMENDED BY THE UNITED STATES STEEL CORPORATION FOR THEIR HEAT-TREATED STEELS. LOW CARBON, LOW-ALLOY HIGH-STRENGTH, AND PROPRIETARY GRADE V-STEELS MET THE MINIMUM REQUIREMENTS OF THE AWS SPECIFICATIONS FOR REPEATED STRESSES. COMPARABLE RECOMMENDED REQUIREMENTS FOR THE HEAT-TREATED STEELS APPEAR TO BE HIGH IN SOME CASES. IN GENERAL, FOR APPROXIMATELY THE SAME RATIO OF TEST STRESS LEVEL TO THE ULTIMATE STATIC STRENGTH, THE LOWER STRENGTH STEELS HAVE LONGER FATIGUE LIVES. WELDMENTS WERE FOUND TO HAVE AS LONG FATIGUE LIVES AS THE CORRESPONDING BASE METALS, EXCEPT FOR THE HEAT-TREATED STEELS. UNDERSTRESSING APPEARED TO REDUCE THE FATIGUE LIFE OF ALL SPECIMENS BUT HAD NO EFFECT ON THE STATIC PROPERTIES. INCLUDED IN THIS REPORT ARE APPENDICES WHICH DEAL WITH METHODS OF OBSERVING THE DEVELOPMENT OF FATIGUE CRACKS, PREVIOUS TESTS OF STRUCTURAL STEELS AND THEIR WELDMENTS, EVALUATION OF SPECIFIED MINIMUM FATIGUE REQUIREMENTS AND SUPPORTING TESTS, DETERMINATION OF FATIGUE STRENGTH REDUCTION FACTOR FOR NOTCHED SPECIMENS AND DERIVATION OF S-N CURVES FOR A36, A242, AND T1-A STEELS.

• Supplemental Notes:
  • Hpr-1/2/, HR-175, JAN65
• Corporate Authors:

  University of Washington, Seattle

  Seattle, WA  United States  98195
• Authors:
  • Payvar, K
  • Vasarhelyi, D D
• Publication Date: 1965-1

Subject/Index Terms

• TRT Terms: Alternatives analysis; Behavior; Cracking; Evaluation; Fatigue (Mechanics); Fatigue (Physiological condition); High strength steel; Minimization; Properties of materials; Reliability; Specifications; Standards; Structural steel; Weld metal; Weldments
• Uncontrolled Terms: A36 steel; A373 steel; Fatigue life; Requirement
• Old TRIS Terms: A242 steel; A441 steel; A7 steel; Establishing; Minima; Sss steel; T1-a steel; V50 steel; V60 steel
• Subject Areas: Bridges and other structures; Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00207740
• Record Type: Publication
• Source Agency: Bureau of Public Roads /US
• Files: TRIS
• Created Date: Oct 1 1994 12:00AM