Which term denotes a bridge composed of several small spans built to cross a valley or busy locality?

• A. Bridge
• B. Fly-over/Over-Bridge
• C. Viaduct
• D. Substructure

Answer: (C)

In bridge terminology, a structure that crosses a valley or busy locality using multiple short spans supported by intermediate piers is called a viaduct. The idea is that the overall crossing is achieved by a sequence of spans linked together, not by a single long span. Each small span rests on piers, allowing the bridge to span long horizontal distances while keeping the deck at a manageable height above the ground or road below. This distinguishes it from a simple bridge, which usually implies one main span. A fly-over or over-bridge is typically a roadway that crosses over another road or obstacle, often at a junction and may be single-span or multi-span depending on the design, but the term viaduct specifically emphasizes a chain of spans across a wide gap. The substructure refers to the components beneath the deck, like piers, abutments, and foundations, rather than the overall type of crossing.