Efficient modal-based method for analyzing nonlinear aerostatic stability of long-span bridges

An efficient method for analyzing the nonlinear aerostatic stability of long-span bridges using a modal formulation is proposed. First, simplified linear version defined as modal-based approach introduced, which evaluates bridge displacements properties and speeds up assessment critical velocity by applying root-finding algorithm. Then, this scheme further developed to identify instability limit point in structures combining FEM analyses with algorithm an outer loop. The effects considering three components wind loads, stays sag effect, structural nonlinearities, aerodynamic initial angle attack, are analyzed discussed. computational advantages proposed its accuracy demonstrated through application examples, including 1 DoF system, models full cable-stayed bridge. collapse mechanism driven stiffness degradation caused deck vertical upward displacements. It has been found that influence features very low when nonlinearities control collapse.