English：

Zhiyin Bridge adopts a double⁃deck layout, the superstructure of the bridge is composedentirely of curved steel box girders, which have large variations in beam alignment and require highprecision. In response to the issues present in existing steel box girder fabrication techniques, such aspoor machining accuracy of parts, large space requirements for pre⁃assembly, and difficulties in onsiteinstallation, a manufacturing and installation technology for steel box girders of double⁃curved bridgebased on BIM technology has been proposed. The process begins with selecting suitable BIM software,followed by BIM software to complete bridge modeling and simulate construction. Then, part informationis exported from the BIM model for layout and cutting. Pre⁃assembly is conducted in the factory using an“N+1” method, and finally, onsite installation is performed. Practice has proven that this technologyeffectively solves the problems associated with poor machining accuracy of curved surface parts of steelbox girders of long⁃span curved bridge, large space occupation during pre⁃assembly, and difficultinstallation. It offers the advantages of strong quality controllability, simplicity and efficiency.