FATIGUE TESTS OF BEAMS IN FLEXURE

This report gave a description and summary of the results of fatigue tests on various types of beams similar to those used in actual structures and subjected to repeated cycles of loads. The tests consisted of subjecting the beams to repeated loads varying from a small load on the beam to the maximum in the cycle. This load cycle was repeated at about 150 cycles per minute until failure developed at some location in the beam. Fatigue data were obtained on 27 different types of beams and a total of 104 specimens were tested. A description of each series with the average fatigue strength obtained for each series at 100,000 cycles and 2,000,000 cycles was shown. The results indicate the following points: 1) The carrying capacity of a rolled beam is considerably higher than that with a fabricated beam of equivelant section modulus. 2) The carrying capacity of a beam with cover plates cannot be increased indefinitely with an increase on cover plate thickness. 3) The use of cover plates on rolled beams appears to be limited to reinforcement jobs where the beam is already in place. 4) Cover plates on beams should be full length or extended past the theoretical cut-off point, so that the stress in the beam at the end of the plate is only about 40 percent of the stress at the center. The stress-raising effect of welding across the ends of partial length cover plates is about the same as that of the longitudinal welds along the edges of the cover plates.

• Corporate Authors:

  American Railway Engineering Association

  59 East Van Buren Street
  Chicago, IL  United States  60605
• Publication Date: 1951

Media Info

• Features: Figures; Tables;
• Pagination: p. 111-129
• Serial:
  • AREA BULLETIN
  • Volume: 52
  • Publisher: American Railway Engineering Association

Subject/Index Terms

• TRT Terms: Beams; Bridges; Fatigue tests
• Uncontrolled Terms: Bridge structures
• Subject Areas: Bridges and other structures; Railroads;

Filing Info

• Accession Number: 00052436
• Record Type: Publication
• Source Agency: Association of American Railroads
• Report/Paper Numbers: Proceeding
• Files: TRIS
• Created Date: Jul 15 1976 12:00AM