Description

Recently, the main bridge of Xiangnv Bridge, the key control project of the EPC project of National Highway 351 in Lanxi, has achieved a major milestone: the steel-concrete composite segment was successfully hoisted! This marks a breakthrough in the construction of the superstructure of the main bridge and lays a solid foundation for the subsequent hoisting and closure of the 89m long large-segment steel box girder.

steel-concrete composite segment was successfully hoisted

Located in Lanxi, Jinhua, Zhejiang Province, Xiangnv Bridge is a key transportation project of Zhejiang Province. The total length of the bridge is 1415.24 meters with a deck width of 29 meters. It is a two-way six-lane bridge with a design speed of 80 km/h. The whole bridge consists of 9 spans. Spanning the Lanjiang River, the main bridge adopts a (110+260+110) m hybrid girder continuous rigid frame bridge with a main span of 260 meters. An 89m steel box girder is arranged at the mid-span of the main span, and the rest of the main girder adopts prestressed concrete structure.

The main girder of the bridge adopts a single-box single-cell straight web section. The cantilever travellers manufactured by Shandong Boyoun Heavy Industry are adopted for the construction of the concrete cast-in-situ cantilever segments, steel-concrete composite segments and steel box girder segments. 

The project faces multiple challenges including water level fluctuation of Lanjiang River during flood seasons, complex loads of the long-span hybrid girder, and high risks of high-altitude over-water operations. Boyoun developed a customized form traveler solution for the working conditions of the project:

In view of the large self-weight of cast-in-situ cantilever concrete segments and steel box girders, partial components of the form traveler are reinforced, and Q355 high-strength steel is selected as the main material to greatly improve the overall strength and rigidity to meet heavy-load construction conditions.

The travelling system adopts a long double-track lightweight rail. The front sliding supports and buckle wheel adopt roller-type structures, equipped with multiple anti-overturning safety protection systems. The form traveler moves forward safely and stably with higher operation efficiency, suitable for cantilever construction of high piers over water.

Form traveler travelling system adopts a long double-track lightweight rail

 Main components of the form traveler are subjected to assembly and static load preload test before delivery to eliminate potential structural hazards in advance. The equipment can be quickly assembled and put into service after arriving at the site, shortening on-site commissioning cycles and ensuring the construction schedule of the project.

Static Load Preload Test 

The successful hoisting of the steel-concrete composite segment overcomes the key technical barrier of steel-concrete connection for hybrid girder rigid frame bridges, and accumulates valuable practical experience for steel box girder hoisting, system transformation and full-bridge closure of the main span.

As a professional manufacturer of form travelers and bridge formwork, Boyoun Heavy Industry provides full-process technical support and on-site services. Working together with the project team to overcome difficulties, we deliver reliable equipment and professional technology to steadily advance the construction of Xiangnv Bridge and help build a high-quality provincial key transportation landmark project.

Gallery