Investigation of Vortex-Induced Vibration of Double-Deck Truss Girder with Aerodynamic Mitigation Measures

Abstract

The long-span double-deck truss girder bridge has become a recommend structural form because of its good performance on traffic capacity. However, the vortex-induced vibration (VIV) characteristics for double-deck truss girders are more complicated and there is a lack of related research. In this research, wind tunnel tests were utilized to investigate the VIV characteristics of a large-span double-deck truss girder bridge. Meanwhile, the VIV suppression effect of the aerodynamic mitigation measures was measured. Furthermore, the VIV suppression mechanism was studied from the perspective of vortex shedding characteristics. The results indicated that the double-deck truss girder had a significant VIV when the wind attack angles were +3° and +5°. The aerodynamic mitigation measures had an influence on the VIV response of the double-deck truss girder. The upper chord fairing and lower chord inverted L-shaped deflector plate played a crucial role in suppressing VIV. Numerical analysis indicated that vortex shedding above the upper deck or in the wake region may dominate vertical VIV, while vortex shedding in the wake region of the lower deck may dominate torsional VIV. The upper chord fairing and lower chord inverted L-shaped deflector plate disrupted the original vortex shedding pattern in both regions, thereby suppressing VIV. This research can provide a foundation for bridge design and vibration suppression measures for large-span double-deck truss girder bridges.

A scientometric research and critical analysis of road-rail bridge

“…Several recent papers have adopted various research methods, especially the combination of experimental technology and numerical simulation. Using experiments to verify the accuracy of numerical simulation, and using numerical simulation to reveal the microscopic mechanism of experimental phenomena, has become a popular research method [9][10][11][12].…”

Research on Mechanism of Vortex-Induced Vibration Railing Effect of Double-Deck Large-Span Suspension Bridge

“…However, excessively small time steps would significantly reduce calculation efficiency. After conducting trial calculations, a time step of 1 × 10 −4 s was selected to meet the Coulomb number requirement [28,29].…”

“…The boundary layer consisted of 12 layers with a linear growth rate of 1.2 for the section and accessory components, with the height of the first layer taken as 5 × 10 −5 mm to ensure a smooth transition of the near-wall mesh [57]. The total number of meshes was 0.22 million, which was sufficient after the trial calculation [28,29]. Furthermore, the Y-plus values of the truss girder section were all less than one, indicating that the mesh division met the requirements of the SST k-ω model [58].…”

“…The VIV of double-deck truss girders has received relatively little attention. Only Yao et al [28] have studied the effect and mechanism of fairing and deflector plates on truss girder VIV. Fang et al [29] have investigated the VIV mechanism of a truss girder through wind tunnel tests and numerical simulations.…”

Study on the Suppression Effect on Vortex-Induced Vibration of Double-Deck Truss Girder by the Spatial Position of the Deflector Plate

“…The vertical VIV of the bridge may be caused by the eddy current behind or above the bridge. Yao et al [31] explored the influence of aerodynamic measures on the VIV of a double-deck truss girder through wind tunnel tests and numerical simulations. The results showed that the upper chord fairing and the lower chord inverted L-shaped deflector plate played a vital role in suppressing VIV.…”