[Explanation] In Luding County, Ganzi Prefecture, Sichuan Province, the swift cliffs on both sides of the Dadu River have always been the moat on the Sichuan-Tibet Highway.

Today, the Luding Dadu River Bridge on Yakang Expressway spans the sky, shortening the time and space distance between the Ganzi-Tibet area and Chengdu.

　　This kilometer-class suspension bridge, known as the "First Sichuan-Tibet Bridge", was completed and opened to traffic at the end of 2018. It has a total length of 1,411 meters and a main bridge of 1,100 meters. It is the largest bridge in China's Tibet-related area.

In order to make this bridge stand in the high-intensity earthquake zone and the complex wind field of the Dadu River Canyon, what world-class problems did the Chinese builders overcome?

　　Tao Qiyu is the person in charge of the design of the Dadu River Bridge in Luding. He told the reporter that when the bridge was planned, they had selected more than a dozen bridge locations on the upper and lower reaches of the Dadu River. They had to avoid the active fracture zone while also taking into account the cost. Breakthrough and innovation in parts and components.

　　[Concurrent] Tao Qiyu, Senior Engineer, Bridge Survey and Design Branch of Sichuan Highway Planning, Survey and Design Institute

　　The (Dadu River) Bridge is located at the intersection of the famous Y-shaped fracture zone and is the most seismically intensive of the kilometer-class suspension bridges.

The composite beam with corrugated webs and the other is a hinged, energy-consuming central buckle, to solve the seismic problem of the concrete tower in the high-intensity earthquake zone.

　　[Explanation] The local complex wind farm environment is another difficulty in the construction of the bridge.

It is understood that the wind field is turbulent, and the instantaneous wind speed can reach 32.6 m/s, which is equivalent to a level 12 gale.

The wind blows obliquely upward from under the bridge, and the wind direction angle is very large.

In order to solve this problem, the design team made a 1:2000 scale terrain model based on the surrounding area of ​​18 square kilometers, and moved it into the wind tunnel laboratory.

　　[Concurrent] Tao Qiyu, Senior Engineer, Bridge Survey and Design Branch of Sichuan Highway Planning, Survey and Design Institute

　　The wind field in the Dadu River Valley is very complicated. First of all, we invited this terrain into the wind tunnel to find an accurate design wind speed, accurately grasp the wind environment of this place, and adopted the measure of upper and lower stabilizers to ensure the bridge. The wind resistance performance.

　　[Explanation] Although the design of the Dadu River Bridge strives for excellence, the complex geological environment still causes considerable difficulties in the actual construction process.

The person in charge of Yakang Expressway told reporters that the difficulties in construction have forced the builders to continuously create new processes and develop new technologies, which not only optimizes the construction process, but also saves time and labor costs.

　　[Concurrent] Zhou Daoliang, General Manager of Sichuan Yakang Expressway Co., Ltd.

　　We have overcome many difficulties in the construction. We used drones to guide the pilot cable across the river for the first time in Sichuan, and used cables to hoist the main girder of the thousand-meter bridge for the first time in the complex wind farm environment on the plateau.

We creatively place the tunnel anchors between the two tunnels and connect them with a cross channel, which overcomes the contradiction of mutual interference during construction.

　　[Explanation] The ingenuity of Chinese builders has also been recognized by the world.

At the 36th International Bridge Conference in 2019, Luding Dadu River Bridge won the "Gustav Linden Shao" Gold Award, which is known as the "Nobel Prize" in the bridge industry.

　　[Concurrent] Tao Qiyu, Senior Engineer, Bridge Survey and Design Branch of Sichuan Highway Planning, Survey and Design Institute

　　The (Dadu River) Bridge is a breakthrough in the kilometer-class suspension bridge in Sichuan Province. At the same time, it is also the largest bridge in the initial section of the Sichuan-Tibet Expressway. It has great reference significance for subsequent bridges and the construction of such long-span bridges.

　　Reporting from Ganzi, Sichuan by reporter Lv Yang, Wangpeng, Liu Zhongjun

Editor in charge: [Zhang Kaixin]