On June 20, 2020, after five years of hard work by nearly 1,000 builders, the cast girder of the Lalin Railway Zangmu Yarlung Zangbo River Double-track bridge was successfully closed, marking the completion of the main project of 120 Bridges across the railway. Zangmu Bridge is located in jiacha County, Shannan City, Tibet Autonomous Region. The bridge spans the Yarlung Zangbo River, which is 66 meters deep, in the upstream reservoir area of the Zangmu Hydropower Station. The bridge has a total length of 525.1 meters and a main arch span of 430 meters. The bridge is located at an altitude of 3,350 meters. It is the highest and longest concrete filled steel tube arch bridge in the world and the first railway bridge across the Yarlung Zangbo River.
In order to make the bridge more adaptable to the local environment, avoid rust and corrosion, and increase the service life of the bridge, the main structure of the Zangmu Bridge is for the first time coated weathering steel, and TH500-NQ-III welding material is used for Q345qENH. Q420qENH adopts Xinyu welding material TH550-NQ-III welding, Xinyu high strength weathering steel welding material makes a contribution to the high-quality development of Bridge construction in China.