On May 18, the main girder of Hejiang Yangtze River Highway Bridge was finished, which is the world's largest “flying swallow”type Concrete Filled Steel Tube Tied Arch Bridge. Sichuan Hejiang Yangtze River Highway Bridge has a main span of more than 500 meters. But why did the builders choose Concrete Filled Steel Tube Tied Arch Bridge?

The view of the bridge from Dukou

The Concrete Filled Steel Tube Tied Arch Bridge is made of a steel tube in which concrete is injected. With the help of the binding force of steel tube on concrete, the overall bearing capacity is improved, while the self weight is reduced, the consumption of steel tube and concrete under the same bridge is reduced. This is a more economic method which can bring down project cost by more than 30%. Compared with other types of bridges, Hejiang Yangtze River Highway Bridge has saved about 90 million yuan in construction and installation.

Fitting the last piece of deck plate of the main girder of Hejiang Yangtze River Highway Bridge

Hejiang Yangtze River Highway Bridge has created a new world record for Concrete Filled Steel Tube Tied Arch Bridge. Its structural system, structural details and construction scheme achievements are another breakthrough in concrete filled steel tube tied arch bridge technology, providing technical support for the more extensive application of concrete filled steel tube tied arch bridge.

An overview of Ganhaizi Bridge on Yaxi Expressway

Sichuan Province is located in a mountainous terrain, with complex topography and geology, while the concrete filled steel tube tied arch bridge has high bearing capacity, material saving and light self weight. These technical advantages solve construction problems well. For example, Ganhaizi Bridge on Yaxi Expressway is the first all steel tube concrete truss bridge. Because of its light weight, it has successfully crossed the high-intensity seismic zone and withstood the test of Lushan earthquake. It is because of the realization of the "win-win" for economy and technology that concrete filled steel tube tied arch bridges are a leading choice for construction of bridges.（By Edina Liang）