Truss Bridge: A Subtype of Beam Bridge

Yes. A truss bridge is a type of beam bridge.

Hierarchy

• Beam bridge: Simplest form—horizontal beam on piers/abutments. Load carried by bending (compression top, tension bottom).
• Truss bridge: Beam reinforced with a truss—triangular framework of members (chords, webs) that distributes loads primarily as axial forces (tension/compression) in the members, minimizing bending.

Why Triangles?

Triangles are geometrically rigid. A truss transforms a deep, heavy solid beam into a lightweight, open web—efficient for longer spans (50–300 m typical).

Common Truss Types

• Pratt, Warren, Howe, K-truss, Baltimore, Pennsylvania (through/camelback/deck configurations).

All are beam bridges at the structural classification level—just with an optimized internal geometry.