en.Wedoany.com Reported - On July 8, the main bridge of the Guanyinshan Interchange on the Xiajin Bridge (Xiamen Section) completed a critical construction milestone. The 10,400-ton mid-section arch rib of the main bridge was precisely lifted 30 meters as a whole and successfully connected and closed with the side arch ribs on both ends. This integral lifting weight of the mid-section arch rib set a world record for the heaviest integral lifting of steel arch ribs in similar bridges.
The Guanyinshan Interchange main bridge is one of the key control projects of the Xiajin Bridge (Xiamen Section), located at a critical position for the transition between the island section and the cross-sea bridge. The bridge adopts a design scheme where a fishbone beam supports the outer ramp bridges, transferring the load of the outer ramp bridges to the main structure through the structural system, thereby reducing direct intervention in the beach area and avoiding the placement of piers on the beach. This structural arrangement imposes high requirements on the arch rib alignment, steel structure assembly, synchronous lifting control, and closure accuracy.
The mid-section arch rib closed this time weighs 10,400 tons, equivalent to lifting an entire oversized steel structure from the assembly position to the design height under controlled conditions. During construction, multi-point synchronous lifting, real-time attitude monitoring, continuous force verification, and control of deformation, deviation, and interface matching of the arch rib during lifting were required. The 30-meter integral lifting is not a simple hoisting operation but a continuous workflow combining heavy steel structures, hydraulic lifting systems, temporary support systems, measurement control systems, and on-site command systems.
After the mid-section arch rib is connected with the side arch ribs, the main load-bearing framework of the Guanyinshan Interchange main bridge is further formed.
Following the closure of the steel arch rib, the project will transition to subsequent processes such as hanger installation and bridge deck paving. Hanger installation is related to the force transmission between the arch rib and the bridge deck system, while bridge deck paving will push the main bridge from main structure construction to the deck system construction phase. For such large-span, complex interchange bridges, arch rib closure is only a key node in structural formation. Subsequent work still requires hanger tensioning, alignment adjustment, deck construction, ancillary structure installation, and system acceptance.
The Xiajin Bridge (Xiamen Section) project itself integrates a cross-sea bridge, land tunnel, and interchange viaduct, with a main line length of approximately 17.3 kilometers. Upon completion, it will serve as an important corridor connecting Xiamen Island with Xiang'an Airport. The completion of the 10,400-ton steel arch rib integral lifting and closure for the Guanyinshan Interchange main bridge marks a new construction phase for the control structure of this interchange and opens up the working face for the continuous advancement of the bridge's upper structure.
