Buffeting response analysis and vibration damping strategies for steel truss arch bridges in the maximum cantilever state

To enhance wind resistance safety for construction personnel and structural integrity, this study investigates the buffeting response and vibration damping measures of a steel truss stiffened arch bridge with a main span of 400 meters during its maximum cantilever construction state. A finite element model was developed, and a three-dimensional pulsating wind field was simulated using the harmonic synthesis method. Time-domain analysis was applied to compute buffeting displacement responses at the cantilever end of the arch rib and the top of the construction buckle tower. Numerical results were compared with wind tunnel tests of a full-bridge model under varying wind speeds, revealing similar buffeting response patterns. At the bridge reference wind speed, predicted peak buffeting displacements were 22.157 and 21.778 cm in the lateral and vertical directions of the arch rib cantilever end, and 16.994 cm laterally at the buckle tower top, with deviations from wind tunnel tests of 13.2%, 10.2%, and 6.9%, respectively. To mitigate these displacements, lateral wind-resistant cables and flexible connections were analyzed. Lateral cables reduced displacements by up to 84.8% at the arch rib cantilever end and 61.0% at the buckle tower top, while flexible cables further reduced responses by up to 76.8%, ensuring enhanced construction safety. The agreement between numerical and experimental results validates the proposed methods, providing a strong basis for wind-resistant design and vibration damping strategies in similar large-span bridges.