Long-span Cfst Arch Bridge Nonlinear Aerostatic Stability Analysis

At the present time, there is a little research work or even no research one on public about the wind-induced lateral torsional buckling stability problem for long-span concrete-filled steel tube arch bridge. After analyzing and introducing the characteristics of this type of bridge and the aerostatics instability mechanism of long-span bridge, describing the finite element analysis method for the geometry non-linearity problems of concrete-filled steel tube arch bridges basing on virtual work principle, discussing expression forms of the element stiffness matrix being in used in the bridge and structure analysis, a new method which is used to solved the aerostatics stability problem for this type of bridge is proposed. Nonlinear influences caused by structure and aerostatics load are included in this method. Compared with the trial results, the numerical results which indicate the torsional buckling instability form of the bridge are presented to demonstrate the accuracy and effectiveness of this method.