The steel frames on both sides of the deep valley extend outward layer by layer, and the giant steel beams slowly move and align at a height of 100 meters. The construction personnel closely monitor the precision measurement and control equipment to complete the final locking operation. The Fenglai Daxi River Extra Large Bridge, spanning the Daxi River Gorge, has reached a critical milestone. The construction team of China Railway Ninth Bridge has completed multiple rounds of high-altitude assembly operations, overcoming multiple challenges such as large height differences and overweight components in the gorge, and successfully completed the closure of all steel-concrete composite beams. The construction of the main steel structure of the entire bridge has been completed, and the subsequent construction team will comprehensively promote supporting projects such as bridge deck paving and guardrail laying. This world record breaking steel arch bridge is about to complete all construction processes and open to traffic.

Grand Canyon Bridge

The Fenglai Daxi River Grand Bridge is located in the deep gorge area of the Daxi River in Wulong, Chongqing, with steep terrain and huge drops. The total length of the bridge is 1136.7 meters, with a main span of 580 meters. The highest vertical height between the bridge deck and the river surface exceeds 310 meters. The total amount of steel used for the entire bridge is 25800 tons. This bridge is the core control project of the Wuhan Liangzhou Expressway. With a main span of 580 meters, it has become the world's largest span steel arch bridge. China Railway Ninth Bridge is responsible for the production and on-site welding and assembly of all steel beams of the bridge. It is a giant bridge built in complex canyon terrain, which intuitively reflects the comprehensive strength of constructing super large bridges in mountainous areas in China.

Breaking the numbers puzzle

The dimensions and weights of various steel components of the bridge have exceeded the conventional standards, with a maximum truss length of 39.5 meters, a height of 18 meters, and a weight of 425 tons per section. The construction adopts a bidirectional symmetrical cantilever assembly scheme, with the longest high-altitude cantilever reaching 319 meters, and the fault-tolerant space for component splicing is extremely small. The project team uses BIM digital twin technology to build a complete 3D modeling and calculation system, and uses virtual simulation to simulate the entire production and lifting process in advance, eliminating construction deviations caused by 2D drawings, stabilizing the overall manufacturing and splicing errors within 2 millimeters, and relying on digital means to solve various technical bottlenecks in the construction of large steel arch bridges in mountainous areas. Keywords: Fenglai Daxi River Grand Bridge, Wuliang Expressway, Chengdu Chongqing Economic Circle

Pathways promote development

The total length of the Wu Liang Expressway, which carries the construction of the bridge, is 37.18 kilometers, with a two-way four lane design and a standard speed of 100 kilometers per hour for vehicle traffic. It is planned to be fully opened to traffic by 2026. After the road is opened, the travel time from Wulong to Liangjiang New Area will be reduced to less than one hour, connecting multiple tourist attractions in Xiannv Mountain and Baima Mountain, and driving the development of cultural and tourism resources along the route. Smooth roads will accelerate the coordinated development of Fuling, Wulong, Nanchuan, and other three regions, promote efficient circulation of various resources in southeastern Chongqing, and provide solid transportation support for the coordinated development of the Chengdu Chongqing economic circle.Editor/Li Xiaohua