The Whole Stability Analysis Of The Cable-stayed Bridge With Single Tower

The cable-stayed bridge with single tower has got more and more recognition because of its economical and aesthetic. But along with the increase of span length, the use of the thin-walled box girder, the use of the high strength materials, the problem of stability becomes especially important. Because of its variant inner force under dead-loading, nonlinear behavior and the correlation between construction method and completed structure, the construction stability analysis and nonlinear analysis that consider those factors become very important in the design of cable-stayed bridge.Take the Jianning Bridge in Zhuzhou as background, this paper attempts to have some contribution on the whole stability. The Jianning Bridge in Zhuzhou is an asymmetric prestressed concrete cable-stayed bridge with single tower and center-laid cables, which main span is 240 meters long, heading the list in Asian. Thus its stability should be given prominence. The main work has been completed as following:1. The finite element methods about the first and the second kind buckling problem of the cable-stayed bridge are expounded in this paper. At the same time, the essential difference of them and the two evaluation criterions about the stability of the cable-stayed bridge are discussed.2. The paper adopts the 3-D finite element program-ANSYS to establish the space model of the Jianning Bridge, then to analyze the linear and geometrical nonlinear whole stabilities under construction.3. The linear, the geometrical nonlinear and the double nonlinear buckling safety factors has been calculated under the several different work conditions, such as the longest of double cantilever, single cantilever stages, the dead loads stage and the stages of two load combinations. Then the buckling solutions are compared and the stabilities are evaluated. After this, considering all kinds of nonlinear factors, the buckling types and the most possible destroyed forms of the representative phases are also pointed.4. The influence of the cable-stayed bridge's whole stability was investigated through the parameter analysis of the material's elastic modulus, the number and the location of auxiliary piers and the spacing of diaphragm plates.