ANALYTICAL MODELING OF FLUTTER DERIVATIVES AS FINITE-ELEMENTS

This paper presents the development of two elements for finite element modeling of cable-suspended bridge flutter derivatives. The first element, a consistent formulation, utilizes the assumed-modes approach in its development with shape functions being identical to those used for a three-dimensional space frame element. The second element, a lumped formulation, simply assigns one-half of the overall load to each member end. To ascertain the effectiveness of the two elements, each is used to analyze a cable-suspended bridge with various flutter derivatives for the lowest wind velocity that initiates flutter. Results indicate that both elements are accurate and computationally cost effective, with the lumped formulation producing lower wind velocities at flutter.