Which term describes a structure where deck acts together with beams to resist loads?

• A. Cantilever
• B. Truss
• C. Composite
• D. Girder

Answer: (C)

Composite action is the idea here: the deck and the supporting beams are connected so they act as a single structural unit. When the deck (usually a concrete slab or metal deck) is rigidly connected to the beams with shear connectors, they share bending and shear forces, increasing stiffness and overall strength. The deck helps resist compression, while the beams handle tension, and together they respond to loads more efficiently than if they carried loads separately. This is different from a cantilever (a projecting member), a truss (a framework of members in tension/compression forming triangles), or a girder (a large primary beam)—none of these by itself implies the deck and beams working together. Hence, the term is composite.