Which bridge type relies on arch action to transmit loads to the supports?

• A. Arch Bridge
• B. Suspension Bridge
• C. Cantilever Bridge
• D. Truss Bridge

Answer: (A)

Arch bridges use their curved shape to convert vertical loads from the deck into compressive forces that flow along the arch to the supports. The arch pushes outward on the abutments, which must resist that horizontal thrust to keep the structure stable. This arch action—compression along the curved path delivering loads to the supports—is the defining mechanism of arch bridges. Other types carry loads differently: suspension bridges transfer most load through cables in tension to towers, cantilever bridges move loads through projecting arms anchored at piers, and truss bridges pass loads through interconnected axial members arranged in triangles. So the distinctive curved-arch load path that compresses the arch and thrusts at the supports makes arch bridges the correct choice.