WIND ANALYSIS OF CABLE-STAYED BRIDGE AND ITS MITIGATION MEASURES

Abstract

The intent of this research is to present a detailed study of various phenomenons’ that induce vibrations in Cable-stayed bridges. The wind load analysis is carried out for a Cablestayed bridge model for Indian terrain conditions. The wind load analysis is carried out on MIDAS CIVIL 2012 to check the behavior of bridge vulnerability against wind forces. It involves the determination of natural frequency of stay cables and profile of the cable under axial tension and self weight of the cable. The dynamic characteristics of a structure can be effectively analyzed in terms of natural modes of vibrations i.e. in terms of natural frequencies and mode shapes. As the model is a 3D Finite element model, a general modal analysis capable to provide all possible modes of the bridge (transverse, vertical, torsion and coupled). As the second part of work appropriate counter measures to mitigate the oscillations are described in this chapter. These counter measures can be implemented at the source, in such a way that the generation of vibration is limited, or at the structure, through the installation of control systems that have the effect of limiting the response.