Static Stability Calculation Of Multi-Pylon Cable-Stayed Bridges

In the design of Bridges across large rivers, cable-stayed bridge has become a kind of very competitive bridge. Because of the bridge instability accidents happen from time to tome, cable-stayed bridge instability problems also has been caused for concern. In recent years to meet the needs of production and life, more and more cable-stayed bridge arise. Because there are many towers in a multi-pylon cable-stayed bridge, the displacement of a tower is not easy to control which make make it become a more soft structure, and has a more likelihood of instability, therefore, it is necessary to study the stability of multi-pylon cable-stayed bridge.The research content of this paper is divided into two parts, the first part of the paper at first introduced home and broad bridge stability analysis research history, and points out that many bridges are destoryed because of instability, this paper expounds the necessity of the stability analysis. And then introduced the influence of the cable-stayed bridge stability nonlinear factors, among which introduces the causes of these factors, mathematics calculation method, and how to eliminate these unfavorable factors. Finally propose the stability analysis methods of cable-stayed bridge which divided into simplified methods and accurate calculation methods. The second part is mainly the multi-pylon cable-stayed bridge model analysis, with a six towers cable-stayed bridge under construction for the engineering background, detailed introduces how the process of modeling in the simulation of the accurate components. Enter the analysis phase after, detailed introduces the structure in the biggest single cantilever, biggest double cantilever, phase dead load, bridge under the influence of live load of elastic stability coefficient, consider geometry nonlinear stability coefficient, consider the double nonlinear stability coefficient, through the comparison of the data, and at last give a safety evaluation of this bridge. Finally considering in a multi-pylon cable-stayed bridge stiffness is always the influence its mechanical properties of the key indicators.It considers the stiffness of the girder and the main tower and stay-cables on the effect on the stability of cable-stayed bridge, draw about the influence of the rigidity conelution.