DYNAMIC ANALYSIS OF CABLE-STAYED BRIDGE

Abstract

The cable—stayed bridges are increasingly becoming popular for spans ranging from 250m to 500m, for their cost effectiveness. There is, therefore, a need to examine the behaviour of such systems in greater detail, both under the action of static and dynamic loads, and reflect the same in their design. In order to further understanding of the system it is well established that a) The deck/girder assembly behaves as a continuous beam elastically supported at points of connection of the cables with the deck, and b) The tower behaves as a tied cantilever to an extent depending upon the pretensioning forces. Further the system behaves in a nonlinear manner primarily due to changes in cable geometry, and to a lesser extent because of the large order of displacements as compared to conventional systems. This study has been directed at a detailed study of the former source of nonlinearity in the system due to both static and dynamic loads. A computer program has been developed for the following a) Static Analysis with Constant Stiffness method and the Tangent Stiffness method for the solution of the resulting nonlinear equations.