Bridge+Structure

=Let's look at some different ways to design a bridge, and learn some words that describe the features of a structure.= || ||
 * =What makes a structure strong or weak?=
 * [[image:http://www.worsleyschool.net/science/files/bridge/beamdiag.JPG width="144" height="79" align="center"]]

beam bridge || A beam bridge is the simplest design. It's very strong over short distances, but isn't strong enough for lengthy ones.

[|Fuller Warren Bridge - Jacksonville, Fl.] || truss bridge || A truss bridge is one where the deck is supported by a network of triangles (the strongest polygons because their shapes cannot be distorted) made from girders; a truss bridge can support heavy loads with a relatively small weight.
 * __Beam Bridges__ **
 * [[image:RRTrussBridgeSideView.jpg width="299" height="154" align="center"]]

[|Firth of Forth -Scotland] [|Grace Memorial Bridge - Charleston, South Carolina] ||
 * [[image:http://www.worsleyschool.net/science/files/bridge/archdiag.JPG width="132" height="71" align="center"]]

arch bridge || In an arch bridge, compression pushes the weight away from the arch and against the side walls and the material of the arch itself. Because it is often a solid structure, there is very little torsion. The Romans were first to build arch bridges, many without any mortar, and some of them still stand today.

[|Crooked River Bridge -Terrebonne, Ore.] [|Gladesville Bridge -Sydney, Australia] [|Le pont du Carroussel -Paris, France]
 * [|Concrete Arch Bridges]**

[|Bayonne Bridge -New York] [|Hell Gate Bridge -Bronx-Queens, New York] [|Sydney Harbour Bridge -Sydney, Australia] ||
 * [|Steel Arch Bridges]**
 * [[image:http://www.worsleyschool.net/science/files/bridge/suspdiag.JPG width="183" height="82" align="center"]]

suspension bridge || A suspension bridge hangs from cables anchored at each of its ends. Towers along the span also help support it. The cables are under tension. The cables hold up trusses, which provide the stiffness necessary to support the deck. Suspension bridges are good for long distances.

[|Akashi-Kaikyo Bridge -Japan] [|Brooklyn Bridge -Brooklyn, New York] [|George Washington Bridge - New York] [|Golden Gate Bridge -San Francisco, California] [|Humber Bridge - UK] [|Mackinac Bridge - Straits of Mackinac, Michigan] [|Verrazzano Narrows Bridge -New York] ||
 * [|Suspension Bridges]**
 * [[image:http://www.worsleyschool.net/science/files/bridge/cablestaydiag.JPG width="156" height="104" align="center"]]

cablestay bridge || The cablestay bridge is the most interesting design; the deck is supported by cables from a central tower. Some //buildings// are now being built this way! Cablestay bridges may be joined to form long spans. The roadway runs on both sides of the tower, so that the stress is applied evenly..

[|Charles River Bridge -Boston, Massachusetts] [|Cooper River Bridge -Charleston, South Carolina] [|Dames Point Bridge - Jacksonville, Florida] [|Greenville Bridge Project -Greenville, Mississippi] [|Le Pont de Normandie Bridge - Honfleur, France] [|�61�Leonard P. Zakim Bunker Hill Bridge�82��62�Boston, Massachusetts�83�] [|Maumee River Bridge -Toledo, Ohio] [|Maysville Bridge - William H. Harsha Maysville, Kentucky] [|Millau Viaduct -France] [|Oresund Bridge - connects Denmark to Sweden] [|Sidney Lanier - Brunswick, Ga.] [|Sunshine Skyway Bridge - Tampa Bay, Florida] [|Talmadge Memorial Bridge - Savannah, Georgia] [|Vasco da Gama Bridge -Lisbon, Portugal] || [|Bridge of Lions (historic) -St. Augustine, Fl.] [|Main Street Bridge (historic) - Jacksonville, Fl.] [|17th Street Causeway -Ft. Lauderdale, Fl][|.] [|Tower Bridge (historic) -London, England] ||
 * [|Cable-Stayed Bridges]**
 * || **[|Movable Span Bridges]**

A cablestay bridge