Preliminary Scope
A complementary bridge deck protection system consists of deck treatments (AASHTO Element 510 Wearing Surface and Element 521 Concrete Protective Coating) constructed together as a system to extend the service life of a deck beyond what either treatment would achieve if used separately.
Once a bridge is constructed and put into service, it begins to deteriorate. One of the most vulnerable bridge components to deterioration is the bridge deck. Decks are often exposed to contaminants and adverse weather conditions (e.g., deicing chemicals, road salts, etc.), water, freeze-thaw conditions, and saltwater environments. Water and contaminants can penetrate concrete and cause accelerated deterioration.
State DOTs undertake various strategies in design, construction, and maintenance to minimize, reduce, and slow the deterioration of their bridges. Many bridge decks have overlays, such as asphalt only, asphalt with a liquid applied waterproof membrane, asphalt with a sheet applied waterproof membrane, rigid cementitious concrete, latex-modified concrete, premixed polymer concrete with primer, multi-layer polymer concrete with primer, etc. These overlays function as protective wearing surfaces that reduce the amount of water and contaminants permeating the underlying deck concrete, thereby increasing the service life of the deck. However, these overlays may obscure the condition and hide deterioration of the underlying deck.
Some state DOTs use overlays in conjunction with deck treatments, such as concrete-penetrating sealers, crack sealers, or healer sealers, or a combination of sealer types. These complementary bridge deck protection systems further extend the service life of decks because the top layer of protection (the overlay) has to fail before the second layer of protection (the sealer) begins to work. Using a complementary bridge deck protection system may give state DOT bridge owners latitude about when to replace the overlay without experiencing significant deck deterioration. The cost of applying a concrete-penetrating sealer, crack sealer, or healer sealer is estimated to be 2% of the cost of replacing a deck, 4% of the cost of a partial-depth deck replacement, and 1% of the cost of new bridge construction. However, even at this relatively low cost, it is unknown how extensively complementary bridge deck protection measures are used.
The objective of this synthesis is to document state DOT practices for the use and design of complementary bridge deck protection systems. The synthesis encompasses current practices for designing (e.g., selecting a deck treatment combination), installing, maintaining, replacing, and successively using complementary bridge deck protection systems to extend the service life of bridge decks.
Information to be gathered includes (but is not limited to):
- Deck protection treatments (overlay or sealer) used as a single (stand-alone) deck protection strategy;
- Complementary bridge deck protection systems used, including the treatments that comprise the systems and the duration of use;
- Factors and constraints considered when selecting and designing appropriate deck protection systems;
- Written policies, guidelines, or specifications for decision-making on individual or complementary deck protection systems;
- Strategies and practices for installing, maintaining, and replacing complementary deck protection systems or individual treatments within the system;
- Criteria used to evaluate performance, and
- Performance of complementary bridge deck protection systems.
Information will be gathered through a literature review, a survey of bridge owners, and follow-up interviews with selected bridge owners for the development of case studies. Knowledge gaps and suggestions for future research to address those gaps will be identified.
TRB Staff
Jo Allen Gause
Phone: 202-334-3826
Email: jagause@nas.edu
Meeting Dates
First Panel Meeting: October 2024 (Date TBD)
Teleconference with Consultant: TBD
Second Panel Meeting: TBD
