Performance of Concrete Bridge Deck Surface Treatments

The purpose of this research was to identify types of surface treatments available for use on concrete bridge decks and to determine which materials are most capable of providing long-term protection from contamination by chloride ions. This research focused primarily on urethanes, silicon-based sealers, and epoxies. An extensive literature review was conducted to document common overlay distresses, performance histories, and properties of specific surface treatment products currently available in the industry, and a nationwide questionnaire survey was conducted to investigate the state-of-the-practice with regard to deck surface treatment applications by state departments of transportation throughout the United States. This research suggests that epoxy-based surface treatments should be specified for concrete bridge decks when both a chloride barrier and improved skid resistance are desired. If a chloride barrier is all that is needed, silane surface treatments should be considered, as they are less expensive and easier to apply than epoxy treatments. When a large amount of epoxy is to be mixed, automatic proportioning equipment should be employed. Because concrete decks with significant cracking are not ideal substrates for polymer applications, surface treatments should be applied as preventive measures early in the service lives of bridge decks to effectively prevent chloride concentrations from reaching critical levels.