What is the portion of the bridge below the bearing that is used for supporting the bridge superstructure and transmits all loads to ground?

• A. Substructure
• B. Bearings
• C. Deck
• D. Girders

Answer: (A)

In bridge design, the load path goes from the deck and superstructure through the bearings into the substructure, then down through the foundations to the ground. The portion below the bearings that supports the superstructure and transmits all loads to ground is the substructure. It includes elements like abutments, piers, and foundations. The deck and girders are part of the superstructure and sit on the bearings, while the bearings themselves are the interface between superstructure and substructure and do not carry loads straight to the ground. Hence, substructure is the correct term.