China News Service, Beijing, November 11 (Reporter Lu Shaowei) On the afternoon of the 28th, the National Highway 28 New Line Expressway Project Anjiazhuang Bridge across the Fengsha Railway Turnaround Bridge successfully completed the turnaround. The bridge is located in Anjiazhuang Village, Wangping Town, Mentougou District, Beijing, and is the world's first pier top double-rotating curve steel truss cable-stayed bridge, spanning Fengsha Railway, Yongding River and National Highway 109.

The picture shows the swivel bridge before turning. Photo by China News Service reporter Tian Yuhao

The bridge is the only turnaround bridge of the new National Highway 109 expressway, and it is also a control and key project of the whole line. The bridge starts from the north side of the Fengsha railway, the left and right lines are laid in frames, the left is a steel truss cable-stayed bridge, with a rotating weight of 15800,9400 tons, and the right is a continuous steel truss girder bridge, with a rotating weight of <>,<> tons. In order not to affect the normal operation of the existing railway and ensure the safety of construction, the project adopts the synchronous rotation method at the top of the pier. After the bridge was successfully turned, it was like a "cloud sail" standing on the Yongding River, adding a new landmark to the western part of the city.

The rotating system of the bridge is located at an altitude of more than 30 meters, which is the "heart" of the rotating construction, and the structure is complex. The 248-meter large cantilever curve steel truss girder is difficult to achieve double-width synchronous rotation and accurate positioning, and real-time monitoring is required.

The rotating engineering adopts an intelligent synchronous control traction system and an intelligent real-time visual monitoring system to monitor the key cross-sectional stress, bridge end displacement, rotation speed, spatial position, traction force and other related parameters of the rotating beam, grasp the status of the rotating bridge in real time, and ensure that the rotation speed of the left and right bridge is synchronized.

The picture shows the rotating bridge in the rotating body. Photo by China News Service reporter Tian Yuhao

According to Lu Xianglong, the project leader, the next step will be a month-long support installation and ancillary construction such as falling beams.

The reporter learned from the construction unit, China Railway Sixth Bureau, that the project began in September 2021, and adopted international advanced technology in the design of the bridge rotating structure, the alternating welding of the pipe string inside and outside, and the hoisting of super-large and super-heavy cap beams.

The picture shows the rotating bridge in the rotating body. Photo by China News Service reporter Tian Yuhao

National Highway 109 Xinxian Expressway is a rapid transportation corridor connecting Hebei and the western part of Beijing, and construction is currently intensifying. The relevant person in charge of Mentougou District said that after the completion of the highway, the mountain road will be changed from "crossing mountains and mountains" to "crossing mountains and mountains". The district will speed up the construction of municipal facilities such as electricity and communications, and build the 109 new expressway into a composite corridor for disaster prevention and relief in the district. (ENDS)