Evaluation of Mechanical and Corrosion Properties of MMFX Reinforcing Steel for Concrete [Summary Report]

Details

• Creators:
  Gong, Lien ; Darwin, David ; Browning, JoAnn ; Locke, Carl E.
• Corporate Creators:
  University of Kansas
• Corporate Contributors:
  Kansas. Dept. of Transportation
• Subject/TRT Terms:
  Corrosion Resistance Epoxy Coatings Geotechnology Highways I34: Steels And Metals Laboratory Tests Materials Materials By Chemical Properties, Composition & Structure Mechanical Properties Reinforcing Steel Tension Tests

  More +
• Publication/ Report Number:
  FHWA-KS-02-8
• Resource Type:
  Brief
• Geographical Coverage:
  United States ; Kansas
• Edition:
  Summary Report
• Corporate Publisher:
  Kansas. Dept. of Transportation
• Abstract:
  The corrosion performance of MMFX and conventional reinforcing steels is compared based on macrocell and bench-scale tests. The conventional steel includes epoxy-coated and uncoated bars. Macrocell tests are conducted on bare bars and bars symmetrically embedded in a mortar cylinder. Specimens are exposed to a simulated concrete pore solution with a 1.6 or 6.4 molal ion concentration of sodium chloride. Bench-scale tests include the Southern Exposure and cracked beam tests. A 15% (6.04 m ion) NaCl solution is ponded on the top of both the Southern Exposure and cracked beam specimens. Mechanical properties are compared with the requirements of ASTM A 615. The uniformity and consistency in chemical composition is evaluated using a scanning electron microscope and an energy dispersive spectrometer. The microstructure of corrosion products is analyzed using a scanning electron microscope. The results indicate that MMFX steel exhibits better corrosion resistance than conventional uncoated steel, but lower corrosion resistance than epoxy-coated bars. In both the macrocell and bench-scale tests, MMFX steel exhibits a macrocell corrosion rate between one-third and two-thirds that of uncoated conventional reinforcing bars, while epoxy-coated reinforcement with the coating penetrated corrodes at a rate between 5% and 25% that of conventional steel. MMFX reinforcing steel is not recommended as a replacement for epoxy-coated reinforcement unless it is used in conjunction with a supplementary corrosion protection system.
• Format:
  PDF
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:02c657411bc08199189613aad3f7282d9dff8aa782286c56c0623052db38dfde
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/39880/dot_39880_DS1.pdf
• File Type:
  [PDF - 36.36 KB ]