Nonlinear Stability-Analysis Of Concrete Filled Steel-Tube Arch Bridge With Respect To Various Horizontal Load

In this paper,the out-of-plane stability of Nan Pu Bridge,which is a long-span concrete filled steel-tube arch bridge,is analyzed by linear elastic analysis and geometrical nonlinear analysis. The analysis shows that the stability factor of linear elastic analysis is approximately equal to the stability factor of geometrical nonlinear analysis .It is also revealed that the stability factor decreases little with respect to various horizontal loads.In order to consider the nonlinear behavior of material,the stress-strain relationship of concrete filled steel-tube structure is introduced in the following research. The analysis result shows that the stability factor of the bridge deceased significantly when the nonlinear behavior of material is considered.To investigate the practical stability performance of this bridge,a model test is carried out. The test model actually simulates Nan Pu Bridge based on similarity criterion. The model test reveals that the stability factors is more than 2.0,so the stability and strength of this bridge have been verified to be met with.