When something pushes down on the
beam, the beam
bends. Its top edge is pushed
together, and its bottom edge is pulled apart.
Every bar in this
cantilever bridge experiences
either a pushing or pulling
force. The bars rarely
bend. This is why cantilever
span farther than
In all suspension bridges, the roadway hangs from massive
cables, which are draped over two
towers and secured into solid
concrete blocks, called anchorages,
on both ends of the bridge. The cars push down on the roadway, but
because the roadway is suspended, the cables transfer the
compression in the two towers. The
two towers support most of the bridge's weight.
The arch is squeezed together, and
force is carried outward along the
curve to the supports at each end. The supports, called abutments,
push back on the arch and prevent the ends of the arch from
Resources on bridges from PBS including...
In addition, a list of
links to information about some of the world's biggest and best
bridges is available.
The NOVA program chronicles the building of the
state-of-the-art Clark Bridge over the Mississippi River.
How Stuff Works
edition of HowStuffWorks, they look at the three major types
of bridges so that we can understand how each one works.
School step by step guide, including photos, of how to
design and build a bridge.
Truss Bridge Design
article explaining the history and principles of truss
bridge design. Several good diagrams.
site from the Deutsches Museum. Great articles/pictures
explaining Arch, Beam, Suspension and Cable-Stayed Bridges.
California Geological Survey - Online Maps and Data
MAGIC: Map and Geographic Information Center
California 30-minute Topographic maps
Geography - Search Results
7.5 Minute DEMs of California
TopoZone - The Web
s Topographic Map and more!
Maps and Mapping Resources
Microsoft TerraServer Imagery
MapQuest.Com Maps, Directions and More
BridgeSite - Fun and Learning
BUILDING BIG: All About Bridges
BUILDING BIG: Databank: Search
It & Bust It: A Webside Construction Zone
The Toothpick Bridge
Project - Rice University - Awesome
searchable database of bridge information
Check out these bridges...
Bridge Designer (On-line Free)
This program allows you to design and test trusses. Trusses are
composed of straight members connected at their ends by hinged
connections to form a stable configuration.
Point Bridge Designer (Free - PC only)
This software will introduce you to engineering through an
authentic, hands-on design experience. WPBD 2003 provides you with
the tools to model, test, and optimize a steel highway bridge, based
on realistic specifications, constraints, and performance criteria.
CyberBee: Fun with Science: Bridges, Bubbles, and
BUILDING BIG: Webography: Bridges
Mrs. Herook, Building Bridges Resource Page -