The Wuxi Fengxiang Road Rapid Transformation Project is constructed by Wuxi Public Engineering Construction Center and designed by SMEDI. The entire line adopts the form of “main elevated road” plus “ground road”, with a total length of 10.3 kilometers. The elevated road is an urban expressway with six lanes in both directions, and the main line design speed is 80 km/h. The project is expected to be completed by the end of 2019. No scaffolding, no cast-in-place, building an elevated bridge is like assembling Lego blocks—this is exactly the application of building prefabrication technology in the field of municipal engineering. In the future, urban bridge construction will mainly adopt prefabricated technology. With its mature application of this technology, SMEDI proposed a fully prefabricated bridge scheme during the scheme research stage of the Wuxi Fengxiang Road Rapid Transformation Project, addressing the actual situation of heavy traffic on Fengxiang Road. “High quality + high efficiency + environmental protection + safety” are the four outstanding advantages of fully prefabricated assembly technology. The construction of fully prefabricated elevated bridges reduces traditional construction methods such as on-site scaffolding, manual tying, and cast-in-place, greatly reducing the labor intensity of on-site workers, ensuring safe operations, and the assembly speed is seven times that of traditional processes.
The prefabrication factory, which “assembles building blocks” in the front and “makes building blocks” in the back, ensures quality controllability through standardized process production and advanced equipment. At the same time, it minimizes the impact on existing traffic and surrounding residents during construction, avoiding side effects such as “noise, dust, and road closures.”
As the first fully prefabricated bridge project in Jiangsu Province, the Wuxi Fengxiang Road Rapid Transformation Project prefabricates all components such as columns, bent caps of the substructure, and box girders of the superstructure in factories, then transports them to the site and uses large hoisting equipment to assemble them like building blocks.
The superstructure of the bridge adopts prefabricated prestressed concrete simply supported small box girders, with a standard span of 30m. The maximum hoisting weight of a single girder is 95 tons.
The pier columns have a rectangular cross-section with rounded chamfers, and the maximum hoisting weight of a single column is controlled to be less than 120 tons.
The pier bent caps adopt an inverted T-shaped cross-section to reduce the height of the substructure and lower the overall vertical elevation of the road. The above columns and bent caps are all constructed using factory prefabrication and on-site assembly.
The foundation adopts bored pile group foundation, with pile diameters mainly of 1.2m and 1.5m. Rotary drilling rigs are used for hole formation, and the piles and pile caps are cast-in-place on site. The substructure and superstructure of the fully prefabricated small box girder structure transfer on-site formwork, rebar tying, concrete pouring, and curing to the prefabrication factory, turning the traditional sequential construction process of foundation-pier-superstructure into parallel processes. Prefabricated components are divided into segments and assembled on site using transport and erection equipment, accelerating construction progress. Compared with traditional bridge construction methods, fully prefabricated bridge technology places higher demands on project management and construction technology. To create a demonstration project of fully prefabricated assembly in Jiangsu Province, SMEDI, in cooperation with the construction unit, provided comprehensive and full-process prefabricated assembly technical consulting services in aspects such as prefabrication factory site selection and scale, transportation schemes, bridge assembly schemes, connection structures and construction techniques, component prefabrication, on-site installation, engineering tests, and team training.

The design team of SMEDI specially formulated construction drawing design specifications and technical regulations adapted to local characteristics, serving as normative documents guiding construction and important basis for quality acceptance. For components and materials used for assembly connections, the design documents not only proposed necessary technical parameters but also specified inspection items and contents. To ensure the connection quality of prefabricated components, notes and effective quality control measures were provided for construction equipment and techniques. Multiple detailed technical clarifications on construction drawings were conducted with the construction unit, and active participation in the review of construction organization design was made.
The SMEDI team required simulation of on-site installation conditions for process tests such as column bedding mortar and sleeve grouting to ensure successful installation in the actual project. In addition, they assisted the construction unit in designing full-scale column specimens and conducted tests on the connection strength between columns and pile caps to further verify the reliability of connection materials and construction techniques.
The hoisting of the first prefabricated pier column completed, kicking off the construction of Jiangsu Province's first fully prefabricated elevated bridge project. SMEDI will continue to provide high-quality service support to create a quality project.