World’s Highest Bridge
January 6, 2017
Motorists in southwestern China can get around a little quicker this week, if they are willing to brave stupefying heights to do so. In late December 2016, the Beipanjiang Bridge opened to traffic after three years of construction. If you are afraid of heights, don’t look down! China’s newest bridge is the highest in the world.
The Beipanjiang Bridge, the world’s highest bridge, soars among the clouds above the Beipan River in southwestern China. Credit: © VCG/Getty Images
As you probably know, a bridge is a structure used by people and vehicles to cross areas that are obstacles to travel. Engineers build bridges over lakes, rivers, canyons, and busy highways and railroads. China’s Beipanjiang Bridge is a cable-stayed bridge. Cable-stayed bridges are similar to better-known suspension bridges. Both types of bridges have roadways that hang from cables, and both have towers. In a cable-stayed bridge, however, the cables that support the roadway are connected directly to the towers, rather than being hung from two or more main cables that span the towers (as is the case with suspension bridges). Suspension bridges usually have only two towers, but cable-stayed bridges often have one, two, or several towers—as many as are needed.
Cable-stayed bridge. Credit: WORLD BOOK illustration
The Beipanjiang Valley plunges some 1,500 feet (500 meters) to the Beipan River below the new bridge, creating the need for a simple, two-tower design. The Beipanjiang Bridge is 4,400 feet (1,340 meters) long, with a main span (distance between the two towers) of 2,363 feet (720 meters). Looking over the side of the bridge’s main span is like looking from the top of Chicago’s Willis Tower to the streets below—a mighty long drop. The Beipanjiang Bridge is an architectural marvel, but it is also practical, greatly reducing travel times between China’s Guizhou and Yunnan provinces.
The Beipanjiang Bridge may be the highest, but it is not the longest. The Akashi Kaikyō Bridge, a suspension bridge in Japan, spans 12,831 feet (3,911 meters). Its main span alone is over a mile (1.5 kilometers) long. The Beipanjiang Bridge is not the tallest bridge, either. The piers (supports that hold towers in cable-stayed and suspension bridges) hug each side of the Beipanjiang Valley, so neither pier-tower structure is particularly tall. The tallest bridge in the world is the Millau Viaduct in France, another cable-stayed bridge. It measures 1,089 feet (332 meters) tall from the base of one its piers to the top of the tower. Drivers crossing the Beipanjiang Bridge won’t care much, however, if it isn’t the longest or the tallest. A simple glance out the car window shows that the ground is a long, long way down.
