Construction monitoring of horizontal eccentric rotation of small-radius curved girder bridges

Curved bridges are increasingly being used as ramp connections for elevated bridges or tunnels on expressways. However, the construction of curved girder bridges is typically more challenging than building straight bridges, as the eccentric configuration introduces imbalanced forces during assembly. This study proposed a construction monitoring technology for the horizontal rotation of small-radius curved bridges, using a real curved steel box girder bridge as a test case. Featuring a radius of 320 m and a total span of 250 m, the bridge was constructed using the horizontal eccentric rotation method as it crosses over the Guangzhou-Shenzhen Expressway. By integrating finite element analysis and theoretical analysis, key parameters of the entire system were determined with high accuracy. The rotation process was simulated using a building information modeling model to prevent collisions and optimize the details of the construction. Particularly, the entire construction process was carefully monitored to guarantee assembly precision and construction safety. The results were reflected in an intelligent monitoring platform in real time and allowed for dynamic control of the construction process. With the optimized construction process and implementation of real-time monitoring, the rotation of the two T-structures lasted for merely 42 mins and the entire project was completed within 95 days. The proposed technology successfully reduced the construction time and cost, and the project established a benchmark example for future applications.