Suspension bridges how stuff works

Suspension bridges how stuff works

How Bridges Work

We are a species of bridge builders. Since time out of mind, humans have engineered structures to surmount obstacles, such as, say, Jiaozhou Bay. The body of water is now home to a 26.4-mile (42.5-kilometer) bridge that links the busy Chinese port city of Quingdao to the Chinese suburb of Huangdou.

Suspension bridges how stuff works

Cite this page

Suspension bridge, bridge with overhead cables supporting its roadway. One of the oldest of engineering forms, suspension bridges were constructed by primitive peoples using vines for cables and mounting the roadway directly on the cables. A much stronger type was introduced in India about the 4th century ad that used cables of plaited bamboo and later of iron chain, with the roadway suspended.

Suspension bridges how stuff works

Why do suspension bridges work?

Suspension bridges work by using a series of towers that have long caternary cables that hang from one tower to another. From these main caternary cables, there are vertical cables that lift up the deck.

Workers at the bridge

The Bridgemaster reports to the Trustees, who are a group of twelve very important volunteers with lots of experience in engineering, law and local issues. The Trustees are the custodians of the bridge and have taken on the responsibility of preserving and maintaining the bridge for the future. 

Golden Gate Bridge Design

Both men reviewed Strauss’s original plans for a symmetrical cantilever-suspension hybrid bridge and found them to be practical from an engineering standpoint and capable of being built. In November 1925, Moisseiff expressed concern about the hybrid design and submitted to Strauss his Report on Comparative Design of a Stiffened Suspension Bridge over the Golden Gate Strait at San Francisco, CA, which describes a design contrasting from the cantilever-suspension hybrid bridge design—a suspension span design.

About this Item

The Library of Congress does notown rights to material in its collections. Therefore, it does not license or charge permission fees for use of such material and cannot grant or deny permission to publish or otherwise distribute the material.

Suspension bridges how stuff works

Keeping You in Suspens(ion)

The Akashi-Kaikyo Bridge, shown in Figure 1, is the longest suspension bridge. in the world, at the time of this writing (January, 2014). The bridge is 3911 meters (m) long overall, with a central span of 1991 m. The bridge is in Japan, where it connects the city of Kobe (on the large island of Honshu) with Iwaya (on Awaji Island, a smaller island in Japan). In addition to the sheer length of the bridge, the engineers who designed it also had to consider the environment: high winds, strong sea currents, salt air, and the potential for earthquakes in the area.

1. Bridges can be friendly to the environment

There are 600,000 bridges in the United States. Millions of people cross them every day. Yet surprisingly, there are many things people don’t know about these complex structures, including the designers, contractors, and maintenance experts who work on them all the time.