Energy budget analysis and engineering modeling of post-flutter limit cycle oscillation of a bridge deck

Experimental Investigation on the Nonlinear Coupled Flutter Motion of a Typical Flat Closed-Box Bridge Deck

“…Positive attack angle 3 • corresponded to more significant drift of heaving static equilibrium position than attack angle 0 • . This phenomenon was also reported by Zhang et al [14] in a numerical study on a flat box bridge deck (side ratio B/D = 12.3) but not mentioned by Amandolese et al [8] in studying the post-critical behavior of a thin plate. The heaving static deformation is probably because of the aerodynamic asymmetry induced by large-amplitude oscillations of instantaneous attack angle.…”

“…where t i is the time point where the torsional displacement α(t) crosses zero axis. The amplitude-dependent aerodynamic damping ratio ξ se can then be obtained by subtracting the structural damping ξ s from the total damping ratio calculated by Equation (14). Figure 13 shows the calculated time-varying damping ratios and frequency during the DTS and GTS processes in Figure 12.…”

“…Experimental and numerical evidences suggest that the aerodynamic nonlinearity under large amplitude will introduce a secondary stabilizing effect and the flutter performance manifests as a soft-type nonlinear flutter instability [2][3][4][5][6][7][8][9][10][11][12][13][14]. When wind velocity exceeds beyond linear flutter boundary, there is a possible existence of nonlinear post-critical limit cycle oscillation (LCOs) due to the aerodynamic nonlinearity.…”

“…The aerodynamic nonlinearities in post-critical states have attracted wide attention in recent years [2][3][4][5][6][7][8][9][10][11][12][13][14]. The reported post-flutter phenomena vary with different deck shapes.…”

“…Up to now, it is still unclear how the coupling of the heave-torsion DOFs evolves with wind velocity and whether the concept of linear mode applies in post-flutter state. In addition, the numerical study by Zhang et al [14] suggests a possible coupling of static deformation during large-amplitude vibration. However, little attention has been paid to this coupling phenomenon.…”