Buffeting Response and Modal Coupling Characteristics of a Curved Suspension Bridge

Curved suspension bridges, known for their elegant geometry and adaptability to complex terrain, are increasingly utilized in modern bridge engineering. However, their intricate spatial configuration significantly alters the dynamic characteristics of the structure, making them particularly sensitive to buffeting responses. This study investigates the wind-induced vibration behavior of a single-tower, single-span curved pedestrian suspension bridge located in Xiamen, China. A finite element model was established, incorporating a simulated turbulent wind field and employing the Scanlan oblique wind decomposition method to perform buffeting response analysis based on Davenport’s quasi-steady theory. Wind tunnel test results were used for validation. The results indicate that under three-dimensional wind loading, vertical vibrations are dominant and strongly influenced by wind direction. Furthermore, power spectral density analysis reveals coupled behavior among the three translational displacement components, highlighting significant vertical-bending-torsional and lateral-bending-torsional coupling effects. Cross-power spectral density and coherence function analyses further demonstrate the multimodal coupling characteristics of the structure. These findings provide a theoretical foundation for the wind-resistant design and structural optimization of curved suspension bridges.