Field Performance of Concrete Deck and Crack Sealants

The main purpose of this project is to conduct an evaluation of deck and crack sealants under actual field conditions in the long term and to perform a life cycle cost analysis of the maintenance of bridge decks with sealants. Deicing salts, mixtures of sodium chloride and calcium chloride, are commonly broadcast over bridge decks during the winter in the Midwest. As ice melts and mixes with the deicing salt, chloride ions can penetrate into the concrete and induce corrosion of the reinforcing bars, or penetrate through cracks and cause deteriorate of the steel or concrete substructure. In recent years, Departments of Transportation have begun using deck and crack sealants as one method to prevent chloride ion intrusion and the subsequent deterioration of the deck or the substructure. Although sealants are commonly used, little is known about their field performance. In a recent study, (Pincheira and Dorshorst, 2005), the laboratory performance of commercially available deck and crack sealants was investigated. It was concluded that the performance of the sealant depended largely on the type and their depth of penetration. This study pointed out that the laboratory evaluation, which followed closely with current standards, may not be representative of the conditions. As a result, sealants with lower depths of penetration could perform well in the field in bridge decks with low abrasion. Therefore, the decision to select an appropriate sealant in practice cannot be based only on the observed performance in the laboratory, but also on its performance in the field and the cost/benefit ratio it provides in the long term.