Bridges & Tunnels (: 

Kintai Bridge, Iwakuni, Japan

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It is a historical wooden arch bridge, located in Iwakuni. Built in 1673, it spans Nishiki River, in a scenic location (at the foot of Mt. Yokoyama, offering great views of the castle above). Destroyed by a flood the next year, it was reconstructed and periodical maintenance included reconstruction of the bridge. It was destroyed again by floods in 1950 and the bridge which stands today was reconstructed in 1953.

    Architecture: The bridge is composed by five sequential wooden arch bridges on four stone built piers as well as two of wooden piers on the dry riverbed where the bridge begins and ends. Each of the three middle spans is 35.1 meters long, while the two end spans are 34.8 meters for a total length of about 175 meters with a width of 5 meters.

    Original Construction: For nearly three hundred years the many versions of the bridge stood without the use of metal nails. They achieved this by careful fitting of the wooden parts and by building up thick girders by clamping and binding them together with metal belts. The main wooden parts of the bridge would then be covered by sheets of copper.


    

Puente de la Unidad In Monterrey Mexico .

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    Overview: The signature structure of Puente de la Unidad project is a 304m (997ft) long asymmetrical cablestayed bridge, with a main clear span of 185.6m (609ft). The main pylon is inclined 30° to the vertical and reaches a total height of 152.1m (499ft) from the top of foundation. Nearly all the main structural components are made of 50MPa (7.25ksi) strength concrete. Thirteen pairs of harped stay cables support
the main span and are anchored on the outside of the roadway. One pair of vertical stays is anchored into the back of the pylon.

    Key Features: Soil was injection grouted for added strength. Foundation was a spread footing and posttensioned in primary directions. Spread footing dimensions were optimized for the monotonic loading. A trapezoidal plan area was designed with a wider toe at the front of the footing. 8000m3 (10500yd3) of concrete used for foundation. Mass concrete casting procedures implemented. Large axial forces at edge beams need to be transferred to central pylon. Well-defi nedload path provided by central and diagonal beams.

http://www.ibtengineers.com/AWARDS/image/IBT-Puente_Unidad.pdf








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http://en.wikipedia.org/wiki/File:Bgabridge.jpg
The Sidney Lanier Bridge is a cable-stayed bridge that spans the Brunswick River in Brunswick, Georgia, carrying four lanes of U.S. Route 17. The current bridge was built as a replacement to the original lift bridge which was twice struck by ships. It is currently the longest spanning bridge in Georgia and is 480 feet tall. It is also the seventy-sixth largest cable-stayed bridge in the world from 2003 - present day. It was named for poet Sidney Lanier.

The Piscataqua River Bridge is a cantilevered through arch bridge that crosses the Piscataqua River, connecting Portsmouth, New Hampshire with Kittery, Maine. Carrying six lanes of Interstate 95, the bridge is the third modern span and first fixed crossing of the Piscataqua between Portsmouth and Kittery
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http://en.wikipedia.org/wiki/File:Piscataqua_River_Bridge_01.jpg
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http://upload.wikimedia.org/wikipedia/commons/6/6d/Eads_Bridge_panorama_20090119.jpg
The Eads Bridge is a combined road and railway bridge over the Mississippi River at St. Louis, connecting St. Louis and East St. Louis, Illinois. The Eads Bridge was also the first bridge to be built using cantilever support methods exclusively, and one of the first to make use ofpneumatic caissons.