Design

The ongoing problem of corrosion of reinforcing steel in bridge decks has been addressed in South Dakota with increased concrete cover over reinforcement and the use of epoxy-coated rebar (ECR). To date, these measures appear to have worked well extending bridge deck life significantly. With the development of new materials and technologies, there maybe a potential for increasing deck life and/or reducing the amount of concrete cover on bridge decks. One of these new materials is MMFX Microcomposite steel. The MMFX Microcomposite steel may be much less susceptible to corrosion than black steel or ECR, and may provide the means of preventing corrosion caused by deicing salts from occurring throughout the life of a structure. At the same time, doubts have been raised concerning the performance of epoxy-coated reinforcement due to failures in high chloride environments (i.e. a marine environment) within three years. Although the first epoxy-coated reinforcement bridge decks constructed in South Dakota exhibit no evidence of deterioration after more than twenty years, an attempt to evaluate their corrosion-resistance in situ was hampered by the lack of chloride ions at steel depth. The purpose of this research is to evaluate the potential corrosion resistance, mechanical properties and uniformity of the MMFX Microcomposite steel using laboratory tests. Based on the results of these tests, South Dakota Department of Transportation (SDDOT) may design, construct and evaluate a bridge deck reinforced with MMFX Microcomposite steel. All test results will be compared with those from epoxy-coated reinforcement and mild steel. The research will provide information on the constructability and effectiveness of MMFX Microcomposite steel for use in bridge decks as well as performance, service life and cost-effectiveness data on both the MMFX Microcomposite steel and ECR systems.

< Back