Orthotropic Steel Deck is characterized by a steel plate with stiffeners, suitable for large-span bridges.

• A. Corrugated Steel Deck
• B. Timber Deck
• C. Orthotropic Steel Deck
• D. Cast-in-Place Concrete Deck

Answer: (C)

An orthotropic steel deck is a steel plate that is stiffened by transverse and longitudinal stiffeners, giving the deck much greater rigidity in the plane of the deck than a plain plate. This directional stiffness—strong in the longitudinal direction where loads travel and controlled in the transverse direction—lets a bridge carry heavy traffic and bending moments with a lighter, thinner deck. Because the stiffness is efficiently distributed through the stiffeners, long-span bridges can use thinner deck and still achieve the required stiffness and load transfer to the girders, making it ideal for large spans.

Corrugated steel deck relies on the corrugations for stiffness rather than a stiffened plate, and timber deck is not a steel system suited for large-span bridges, while cast-in-place concrete deck is a concrete system, not a steel plate with stiffeners.