PARAMETRIC STUDY ON SUSPENSION BRIDGES

Abstract

A Large number of suspension bridges can be found in the hilly areas of India and its neighboring countries like Nepal. The erection of a suspension bridge is simple and the technology required for it is less demanding. The lightness of a suspension bridge and its simplicity of erection makes the suspension bridge a good choice for such a terrain. To make the bridge lighter, the designers use reverse cable and windguy cables. The purpose of the wind cable is to resist the wind loads. The reverse cable keeps the geometry changes of the bridge within limits, when the superimposed load is uneven. The reverse cable also helps to reduce vibration. This thesis investigates the effect of reverse cable on the structural action of a suspension bridge. The parameters considered for this purpose are the initial prestress in the reverse cable and the area of reverse cable. Since cables are involved, the analysis performed is nonlinear static analysis (geometric nonlinearity). The analysis is done using commercially available finite element software called "ANSYS". The results of the analysis are presented in the form of graphs. Analysis is also done for the wind cable of the footbridge, to see the effect of prestress. A number of useful conclusions have been drawn. The results presented here, the discussion of results and the conclusions will give useful insight into the behavior of reverse cable, to the practical designer.