University of Virginia Library

STRUCTURES

MAJOR STRUCTURES:

 

Bridges: -over streams, broad water -grade separations -elevated roadways -pedestrian crossings -bike crossings -railroads

Tunnels: -mountain ridges -ship channels -urban centers -airports

MINOR STRUCTURES:

 

Drainage: -culverts -diversions -impoundments

Other: -cribbing -retaining walls -cattle crossings

MISCELLANEOUS STRUCTURES:

       

Dams	Weigh stations	Emergency access
Breakwaters	Overhead signs	Lighting systems
Truck escape ramps	Cattle guards	Guardrails
Entrance gates	Maintenance access

DESIGN FACTORS:

a.

• Resistance to temperature changes, earthquake, bouyancy, earth
  pressure, erosion from chemicals or stream sediments, ice load

b.

• Live loads - weight and dynamics of vehicles including impact

  Dead loads - weight of structure itself

  Wind loads - may include flooding, ice, currents

c.

• Standard specifications for vertical and horizontal clearances

d.

• Special uses: heavy vehicles, railroads, saddle stock, construction
  equipment

BRIDGE TYPES:

         

Deck slab	spans up to 60 ft.	Note: Timber may be used for spans up to 20 feet.
Girder	spans up to 150 ft.
Truss	spans up to 300 ft.
Arch	spans up to 300+ ft.
Suspension	spans up to 1000+ ft.