Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Built Environment (hierarchy name)
4. Single Built Works (hierarchy name)
5. single built works (built environment)
6. [single built works by specific type]
7. [single built works by function]
8. transportation structures
9. [transportation structures by form]
10. bridges (built works)
11. [bridges by form]

Narrower term/s

• continuous bridges
• deck truss bridges

Anotations

Scope note:

Bridges that employ trusses, which are structural members comprising straight pieces of metal or timber forming a series of triangles lying in a single plane, thus making the structure unlikely to be distorted by stress. Wooden truss bridges, in the form of covered bridges, were common in the United States from the 1870s to the 1930s; carefully fitted timbers were combined with iron rods for tension. Later, railroad bridges and other bridges were constructed of cast iron and wrought iron, which were eventually succeeded by steel in truss bridges.