China's new Changtai cable-stayed bridge breaks several records

China has built the world's longest cable-stayed bridge in the eastern Chinese province of Jiangsu with a length of 10.3 km within six years. The bridge, named Changtai, crosses the Yangtze River and shortens travel times between Changzhou and Taizhou by around an hour. This is according to a Facebook post by China Communications Construction on Tuesday. The bridge has since been opened to car and rail traffic.

The Changtai Bridge – derives its name from the two cities of Changzhou and Taizhou, which the bridge connects – sets several records as a cable-stayed bridge. With a sheer length of 10.3 km, it is the world's longest cable-stayed bridge. Its bridge towers are 350 m high, which is roughly equivalent to the height of a 120-storey building. The main span of the bridge is 1208 m.

It is also the longest road-railway steel truss arch bridge that combines car and rail traffic. The bridge also has a special feature: while railroad tracks on a bridge usually run in the middle between the car lanes of the respective directions, the Changtai Bridge has railroad and car lanes for both directions on two levels, one above the other. Trains can travel at speeds of up to 200 km/h on the route.

The bridge also holds the record for the longest continuous steel truss length.

Technical challenges during the construction phase

The construction of the bridge presented the project team with a number of major technical challenges, writes the South China Morning Post (SCMP). For example, an intelligent tower crane with a lifting capacity of 10,000 metric tons had to be developed in order to be able to move the heavy loads. This made it possible to use huge steel-concrete composite masts and thus speed up the construction time. The engineers also developed one of the world's largest deck cranes, which can place extremely heavy components with millimeter precision.

The structure itself consists of bridge towers whose connecting bridge sections are held in place by numerous steel cables. The strong current of the river posed particular difficulties for the designers. The foundations had to be designed and reinforced to be more stable than originally planned. The diamond-shaped bridge towers consist of a mix of steel and concrete. This ensured a high level of stability while at the same time providing the necessary flexibility to adapt to changes in temperature.

With its architecture, the Changtai Bridge is the first bridge over the Yangtze to combine an expressway for cars, a conventional road and an intercity railroad line in one bridge. It connects the two cities of Changzhou and Taizhou on opposite banks of the river. A journey used to take 80 minutes. The bridge now reduces the journey time to 20 minutes. The Chinese authorities hope that this will also stimulate the economy in the Yangtze delta.

(olb)