The Akashi Kaiyko Bridge

THE WORLD’S LONGEST BRIDGE

The Akashi Kaiyko Bridge in southern Japan is the world’s longest

bridge. The Akashi Kaiyko Bridge spans the Akashi Strait, connecting Awaji

Island to Kobe, an important industrial center. The bridge has a span of 5973

feet (1991 meters), making it over 25% longer than its nearest competition: the

Humber Bridge in England. Strangely, there may be longer bridges in the world,

but the Guinness Book of World Records measures the longest bridges

according to their record-breaking spans.

The Akashi Kaiyko Bridge is a suspension bridge. This means that the

roadway is suspended from pillars by cables.

The concrete pillars have to be tall enough to support the whole weight of

the bridge. The pillars on the Akashi Kaiyko Bridge are 900 feet tall. These

pillars had to be built to withstand not only huge waves but also high-speed

winds, and possibly even violent earthquakes, which are not uncommon in the

area. The bridge has survived one earthquake already: its span was extended by

more than 3 feet by the Kobe earthquake of 1995.

The cables weigh 50,000 tons and have a diameter of almost four feet

each. Each cable contains 290 hexagonal strands; each strand is composed of

127 steel wires. The total length of the wire used is more than 200,000 miles,

enough to circle the Earth 7.5 times!

The first plans to connect Kobe to Naruto via Awaji Island were voiced in

1955, but it took the government thirty years to decide to really build the bridge.

The next three years were spent surveying the site and construction commenced

in 1988. In designing the bridge, special consideration was given to its effect on

the surroundings, great emphasis was placed on a “pleasing balance between

light and shade” and also on the choice of the perfect color.

The construction of the bridge was a very complicated and

technologically draining process, which took ten years to complete. Casting

concrete in 300 feet of water, installing special pilot ropes over the strait by

helicopter, and finally stretching the gigantic steel cables surely wasn’t an easy

job. Ten years after construction commenced in 1988, the bridge was finished

and the six-lane highway finally opened to traffic.

The bridge has made the transportation from island to island much easier,

so in addition to breaking a record, the Akashi Kaiyko Bridge achieves the main

goal of a bridge: to connect two places.

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