What characteristic makes orthotropic decks integral with the steel superstructure?

Orthotropic decks are specifically designed to act as structural components that contribute to the overall integrity of the bridge. One of their key features is their role as the top flange of the entire floor system. This characteristic means that the deck is not just a surface upon which vehicles travel but is integral to the overall load-carrying capacity of the bridge.

In an orthotropic deck, the design allows for the distribution of loads directly through the deck into the supporting girder system. By functioning as the top flange, the orthotropic deck helps to form a composite action with the steel girders below, enhancing the load-bearing capabilities of the entire structure. This synergy between the deck and the superstructure is crucial for maintaining the safety and performance of the bridge over its lifespan.

This approach contrasts with other materials like wood, which do not provide the same structural benefits as orthotropic decks made of steel or concrete that contribute to the overall floor system. The unique design and structural integration of orthotropic decks make them essential for modern bridge engineering, particularly in heavy-load applications.