Which of the following is NOT one of the three main components of a bridge?

• A. Deck
• B. Wearing Surface
• C. Substructure
• D. Superstructure

Answer: (B)

The main concept here is distinguishing the primary structural parts of a bridge. Bridges are typically described by three main components: the deck, the superstructure, and the substructure. The deck is the part you drive or walk on and includes the traffic surface and its supporting layers. The superstructure carries the load from the deck and transfers it to the foundations, and it includes girders, beams, arches, and other load-bearing elements. The substructure comprises the foundations, piers, and abutments that transfer those loads into the ground.

The wearing surface sits on top of the deck as a finishing layer to provide a smooth, durable riding surface and protect the deck material. It is not considered a separate main structural component like the deck, superstructure, or substructure. So the wearing surface is not one of the three main components.