Large-span Arch Bridge Stability Study

Arch bridges constitute a major component in the long-span bridge category because of its high bearing capacity, efficient utilization, saving, low cost and aesthetics. However, arch bridges transmit the applied loads to axial force mainly, which makes arch bridge uniquely susceptible to buckling failure, especially with the slender arch ribs and stiffness decreased.It is said that stability could not be calculated when width-to-span ratio more than 1/20 in JTG code, but the influence appear to be absent in the literature, this study indicate how change buckling safety factor with various width-to-span ratio through numerical analysis of the long-span concrete arch bridges. Furthermore, from the stability analysis of the X-type double ribs arch bridge, this paper show how changes inclined inward angle would affect the stability, and the optimum design is presented. The stability of real arch is the second type that is belong to nonlinear, safety factor will be overrated in linear theory, so nonlinear behavior in calculation is evaluated in this study. Finally, according to the real project, design and construction stability analysis of concrete arch with stiff skeleton of concrete-filled steel tube is investigated, which prove its rationally.Base on the conclusion of study at home and abroad, directed against stability of long-span arch, this study, guided from numerical analysis, provides for theoretical direction to the people engaged in the near type arch bridge engineering after detailed analysis of the design and construction method of the real project.