At 00:30 on October 11, after 70 minutes of intensive construction, the T-shaped swivel girder of the extra-large bridge over the Jiaozuo-Liuzhou Railway on the newly built Dangyang-Yuan'an Railway, undertaken by China Railway 20th Bureau Group, completed an "elegant turn" of 56 degrees clockwise and successfully finished its high-altitude rotation. Since then, construction of the "green channel" for phosphate ore transport in northwestern Hubei has entered an "acceleration phase."

The main line of the Dangyang-Yuan'an Railway is 61.68 kilometers long, with 65 new bridges and 25 tunnels, and bridges and tunnels together accounting for 49% of the total length. It connects Dangyang City and Yuan'an County in sequence, serving as a new channel for the development of phosphate ore resources in northwestern Hubei and as a branch freight railway serving the Yuan'an Industrial Park and the economic development of areas along the line. The extra-large bridge over the Jiaozuo-Liuzhou Railway on the newly built Dangyang-Yuan'an Railway is 1,296 meters long. The continuous girder of the bridge rotated this time is a cast-in-place prestressed reinforced concrete box girder on falsework, 97.2 meters long and weighing 4,000 tons in total, with a rotation system installed at the base of the pier to achieve swivel construction.

Dangyang-Yuan'an Railway construction site

"The construction area is adjacent to the operating line of the Jiaozuo-Liuzhou Railway, a busy trunk railway carrying nearly 100 pairs of passenger and freight trains per day, with dense existing pipelines and equipment and high safety risks," said Sun Peng, project manager of the Dangyang-Yuan'an Railway project of China Railway 20th Bureau Group. During construction, in response to multiple difficulties such as the high risks of construction on an existing line for the swivel girder, the short effective working time, the large variations in soft soil geology, and the special structures, the construction team adopted a four-in-one safety and quality prevention and control system of "system prevention, technical prevention, physical prevention, and personnel prevention," effectively promoting the smooth progress of the project.

The construction area is adjacent to the busy operating line of the Jiaozuo-Liuzhou Railway

The construction team focused on risk control, strengthened risk assessment, implemented safety management responsibilities, monitored key safety points, and reinforced process control. By building a quality management system matching objectives, responsibilities, regulations, methods, and control, it achieved "no blind spots in information transmission, full coverage of education and training, no omissions in responsibility implementation, and no deviation in plan execution," realizing "zero tolerance" in management, "zero accidents" in safety, and "zero defects" in quality, ensuring that the construction process was safely, stably, and controllably managed. The project also carried out solid hazard identification and practical emergency drills to eliminate safety hazards to the greatest extent and safeguard swivel construction safety.

"We have established a regular communication and liaison mechanism with the railway department. In line with the schedule targets, we have broken down the construction plan to specific time points, ensuring the schedule while guaranteeing the operational safety of trains on the existing line," said Yao Zhuo, chief engineer of the project.

The swivel girder achieves precise alignment

To accelerate the construction of the swivel girder of Pier No. 38 of the extra-large bridge over the Jiaozuo-Liuzhou Railway and open up the girder erection channel for the Dangyang-Yuan'an Railway, the project team ensured that the swivel girder was rotated on time and smoothly by adding professional technical personnel, conducting professional knowledge training, and continuously optimizing and verifying the special construction plan.

The Dangyang-Yuan'an Railway extra-large bridge over the Jiaozuo-Liuzhou Railway after precise rotation

The Leizu Station in the project section undertaken by China Railway 20th Bureau Group also connects to the Yangliu phosphate mining area in Yuan'an County, one of the most resource-rich phosphate mining areas in all of Asia. Once completed, the project will be of great significance in promoting regional economic and social development and rural revitalization.