FATIGUE OF WELDED STEEL STRUCTURES

A SUMMARY IS PRESENTED ON FATIGUE IN WELDED STEEL MEMBERS. FATIGUE FAILURES MAY OCCUR IN STEEL AFTER MANY CYCLES OF LOADING. USUALLY, AT TIME OF FAILURE, CALCULATED NOMINAL STRESSES ARE FAR BELOW THE TENSILE STRENGTH OF THE METAL. SUCH FAILURES ARE GENERALLY PROGRESSIVE. THEY START WITH A SMALL CRACK THAT GRADUALLY PROGRESSES THROUGH THE METAL, AND THE FRACTURE IS OF A DULL, SILKY AND EXTREMELY FINE GRANULAR STRUCTURE. IT IS POINTED OUT THAT IN WELDED MEMBERS AND CONNECTIONS, FATIGUE FAILURE MAY OCCUR EITHER IN THE WELDS OR AT STRESS RAISERS IN THE BASE METAL. WELDING MAY CREATE STRESS CONCENTRATIONS IN THE BASE METAL. AS A RESULT, WELDED JOINTS THAT MAY BE DESIGNED TO FAIL IN THE WELD METAL UNDER STATIC LOADING MAY FAIL IN THE BASE METAL UNDER FATIGUE LOADING. THIS IS ESPECIALLY TRUE IN THE CASE OF FILLET WELDS. IT IS SUGGESTED THAT LOWER ALLOWABLE STRESSES BE USED FOR STRUCTURAL MEMBERS AND CONNECTIONS SUBJECTED TO REPEATED LOADING TO REDUCE FATIGUE FAILURES. A NUMBER OF SUGGESTIONS ARE MADE FOR IMPROVING THE FATIGUE STRENGTH OF WELDED JOINTS AND CONNECTIONS.

• Supplemental Notes:
  • Vol 174, No 11, PP 201-204
• Corporate Authors:

  WELCH, SAMUEL C.

  ,    
• Authors:
  • Munse, W H
• Publication Date: 1965-3-18

Subject/Index Terms

• TRT Terms: Accelerated tests; Base metal; Failure; Fatigue (Physiological condition); Fillet welds; Fracture mechanics; Joints; Repeated loads; Steel structures; Stress ratio; Stresses; Surveys; Tensile strength; Weldments; Welds
• Uncontrolled Terms: Stress concentration; Welded joints
• Subject Areas: Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 00216145
• Record Type: Publication
• Source Agency: Engineering News-record
• Files: TRIS
• Created Date: Jun 15 1994 12:00AM