What Are Composite Bridge Decks?

Weight

• Compared to traditional bridge deck building materials, composite bridge deck panels are lighter in weight. The reduced weight of these panels may facilitate ease of construction, and may reduce the weight load on columns supporting a bridge. Reduced weight load on support columns may increase the lifespan of these bridge elements, and reduce the life-cycle cost of the bridge.

Ease of Construction

• Bridges containing composite decks may be easier to construct than bridges made from traditional materials. During the manufacturing process, composite decking members are formed and bonded with polyurethane adhesive to form panels that are typically the width of the finished bridge. This means that construction workers must place and join the panels, instead of forming the panels at the construction site. The lightweight nature of composite bridge decking panels also facilitates ease of construction because they can be moved and set up more quickly than steel or concrete beams.

Cost

• The cost of building a bridge with composite decking materials can be higher than constructing a bridge with traditional materials. A bridge containing composite decking materials may cost almost three times as much to construct than a bridge with a concrete deck, according to the Illinois Department of Transportation. However, composite decking materials can be used to strengthen and repair existing bridges, which may help avoid the cost of complete bridge demolition and reconstruction.

Considerations

• Although composite bridge decks have advantages over traditional deck-building materials, they may also pose challenges. The light weight of composite decking elements may be aerodynamically unstable, particularly for long-span bridges. The quality of composite decking panels may vary according to the manufacturing process. Also, these panels may require a bonded overlay to improve service life and traffic traction.