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Section 5 Applying Technology: Producing Products and Structures
The kind of superstructure a bridge has
indicates the type of bridge it is. The types
of bridges are beam, truss, arch, cantilever,
and suspension. See Figure 17-25.
Beam bridges
Beam bridges use concrete or steel
beams to support the deck. This type
of bridge is widely used when one road
crosses another one. Beam bridges are very
common on the interstate highway system.
Truss bridges
Truss bridges use small parts arranged
in triangles to support the deck. These
bridges can carry heavier loads over longer
spans than beam bridges can. Many rail-
road bridges are truss bridges.
Arch bridges
Arch bridges use curved members to
support the deck. The arch can be above
or below the deck. Arch bridges are used
for longer spans. One of the longest arch
bridges spans more than 1650′ (502 m).
Think Green
Green Architecture
You may not think about this, but buildings consume a lot of resources. Build-
ings consume a great deal of electricity, water, and raw materials. They also output
a large amount of waste and carbon dioxide. Through the practice of green architec-
ture, the resources and waste are greatly reduced. Green architecture is a means
of being more environmentally responsible with buildings from design to construc-
tion and landscaping. Buildings are designed to be more efficient with their use of
resources, starting with the building materials.
Green architecture may use recycled materials in construction. This type of
architecture also uses more energy-efficient resources and renewable energy
sources. It is responsible in planning for landscaping, in order to consume less
water. And while green architecture benefits the environment in general, even the air
and water quality within the building may improve.
Abutment
Pier
Span
Water
Earth
Piles
Deck
Figure 17-24. The parts of a bridge. An
arch bridge is shown in the photo.
American Electric Power Co.