The Cangrong Xunjiang Bridge in Guangxi, constructed by the Wuhan-based central enterprise CCCC Second Harbor Engineering Co., Ltd., opened to traffic smoothly on February 28, 2026. The Xunjiang River flows eastward with green hills facing each other on both banks. This single-column three-tower spatial cable suspension bridge with the world's largest span stretches across the river like a steel rainbow, creating a convenient passage between Cangwu and Rongxian.

The bridge has a total length of 1,688 meters, with a central tower height of 108.9 meters and dual main spans of 520 meters each. It is China's first three-tower spatial cable suspension bridge with a main span exceeding 500 meters. As a key control project of the Cangwu-Rongxian Expressway, it has achieved multiple domestic firsts:It is the first to adopt double deep-groove saddle and pile-wall composite structure anchorage foundations, and the first among domestic three-tower spatial cable suspension bridges to use the cable-before-girder construction method. Over nearly four years of construction, the project overcame a series of technical challenges including deep water, tall towers, and spatial cables.

In the early stage of construction, the pile foundation work for the central tower in the river encountered severe challenges. The Xunjiang River has busy shipping traffic, and the bedrock at the central tower site is hard slate, making it difficult to drive steel pipe piles. The project team brought in a 30-ton hydraulic impact hammer and added 10-ton concrete test blocks to stabilize the working vessel, taking 4 hours to firmly drive the steel pipe piles into the riverbed. Meanwhile, the bridge is adjacent to a drinking water source protection area and wild protected fish habitats. To eliminate pollution, the team abandoned traditional mud slurry technology and innovatively adopted clean water drilling technology, using large amounts of clean water to carry drill cuttings and recycle them. In just one month, 14 super-large-diameter pile foundations were completed, with both the inspection pass rate and the proportion of Class I piles reaching 100%.

To protect the ecology, the bridge's anchorage foundation was the first in China to adopt a pile-wall composite structure, with pile verticality required to be controlled within 1/400, far exceeding industry standards. Facing complex geology, the team developed a drill bit guiding device, adding a "navigation" centering ring to the drill bit, drilling in stages with precise centering, like carving concentric circles in underground rock strata. Ultimately, all 96 anchorage pile foundations were completed with high quality, laying a solid foundation for the bridge.

The central tower of a three-tower suspension bridge is critical to load-bearing, and during girder lifting construction, the main cable is prone to slipping at the tower top. The team independently developed an assembled limit cable clamp, fastening the main cable with tie rod assemblies, like installing a "safety bolt" for the bridge, successfully solving the main cable anti-slip challenge. This technology won a national invention patent and the Gold Award at the China Highway and Transportation Society Micro-Innovation Competition.

During the bridge closure phase, the deep-water bare rock geology of the Xunjiang River made it impossible to fix floating crane vessels. The team self-made 12 heavy anchor blocks weighing 18.6 tons each and sank them to the riverbed, cleverly utilized shore-based anchoring, adjusted anchor casting distances, and coordinated auxiliary vessels applying reverse force for precise positioning. In the early hours of March 27, 2025, builders seized the low-temperature window period and successfully completed the lifting of the last steel box girder, achieving precise closure of the bridge.

A long rainbow lies across the waves, and a new passage opens. The opening of the Cangrong Xunjiang Bridge greatly improves travel efficiency for people on both banks and serves as an important link connecting southeastern Guangxi with the Guangdong-Hong Kong-Macao Greater Bay Area. With craftsmanship-driven engineering supporting regional coordinated development, it plays a Guangxi movement in building a transportation powerhouse.

Source:China Daily Hubei Reporter Station