Currently, the Department utilizes linseed oil/mineral spirits treatments as a penetrating deck sealer on older decks and applies epoxy treatments to random cracking, especially on overlays, where the incidence of cracking is light to moderate. For severe cracking problems we are currently employing a thin epoxy chip seal developed by SDDOT for sealing entire decks, which still allows moisture transport through the deck. Other treatments such as silanes are available as well. We have sufficient tools for sealing cracks on decks but lack guidelines as to which particular treatment strategy is appropriate for a given set of circumstances. For example, what sealing strategy should be applied to a brand new deck with widespread cracking and significant crack widths? This research project will address these questions as well as provide optimum timing strategies for maintaining serviceability and maximizing deck life.
Findings: This project investigated potential concrete bridge deck crack and surface sealers, and their optimum application timing. The purpose of this project was to determine if there were better products than what SDDOT was using (i.e. – linseed oil surface sealer and epoxy crack sealer) that can be applied by SDDOT maintenance personnel.
The objectives and tasks for this project were accomplished by gathering and evaluating agency, field, laboratory, and literature data. A major portion of this research project focused on determining the optimum timing for treatment application.
The results indicate the following:
1. SDDOT should discontinue use of linseed oil as a penetrating sealer.
2. SDDOT should adopt penetrating sealers such as silanes/siloxanes/siliconates for surface sealing.
3. SDDOT should continue to use crack sealers such as reactive methacrylates, modified polyurethanes, and epoxies with low viscosity (i.e. - = 15 cp)