Vibrações não lineares e estabilidade de torres estaiadas

Abstract

This work presents a study and a mathematical model development, in one direction, that describes the non-linear dynamic behavior of cable-stayed towers subjected to the action of both uniformly distributed lateral loads along the length of the mast and concentrated axial loads. Initially a study of the integral-differential equations of motion related to the mast towers, obtained by the extended Hamilton principle and the Galerkin procedure, is made. After, the development of the equations related to the stresses applied on the cables, considering the effect of the protension in the incomplete catenary, is shown. Finally, the compatibilization between the equations that describe the mast towers dynamic motion and the equations associated with the cable forces, is performed. The work present numerical examples of possible situations involving mast, cables and the tower-cable assembly. In order to solve the problems related to the vibration and structural stability of the nonlinear dynamic system, numerical analyzes are performed by using, as the main tool, the Runge-Kutta method. The importance of this work is found in the small amount of research focused on the behavior of cable-stayed towers, in addition, few Brazilian Institutions dedicate to this study.