Experimental investigation of the effect of surface markings on the mechanical integrity of weathering bridge steels.

Details

• Creators:
  Manuel, Michele V. ; George, Edward
• Corporate Creators:
  University of Florida
• Subject/TRT Terms:
  • Weathering steel
  • Bridge construction
  • Fatigue (Mechanics)
  • Milling
  • Plasma arc cutting
• Publication/ Report Number:
  BDV31-977-02
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States
• Corporate Publisher:
  Florida. Dept. of Transportation
• Abstract:
  High-strength low-alloy (HSLA) weathering steels are the conventional material used for non-redundant fracture-critical members in bridge construction. Guidelines have been put in place by state ; Departments of Transportation (DOTs) to prevent material suppliers from making scribe marks that ; will remain on the surface of fracture-critical members when in service, due to the possibility of ; degrading mechanical properties. Currently, any automated scribing marks allowed, namely ; mechanical milling, are either cut off of the member or subsequently welded over, thereby effectively ; removing them prior to service. All other markings are either manually die-stamped or spray-painted ; on. The lack of an automated capability to place markings on weathering steels slows production, and ; markings are often accidentally removed during sand blasting or shipping, which causes additional ; problems for the manufacturer and recipient. There is a need to establish safe, automated methods of ; scribing fracture-critical members such that markings will remain throughout the production process, ; but will not compromise the integrity over the lifetime of the part. Three automated techniques were of ; interest in this study as they are often already in the manufacturing process. These include mechanical ; milling, plasma scribing, and laser scribing. In this study, a microstructural evaluation of 50W ; weathering steel was conducted to understand and characterize the effect of the three markings on ; microstructural evolution and mechanical properties. Plasma scribing resulted in the most noticeable ; surface marking. S-N curves generated through fatigue testing showed no measurable difference in ; fatigue life between marked and unmarked material.
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• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/28411/dot_28411_DS1.pdf
• File Type:
  [PDF - 14.38 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:1e57a7034ee9da67c736f0dba2aeca6c5f5c11959bd81c0b2b582abb16cffee3