Aeroelastic behavior of very long span suspension bridges

Abstract

The main purpose of this assignment has been to obtain and understanding of the challenges concerning a future very long span suspension bridge across Sognefjorden. I have through studies of existing literature and similar bridge-projects identified the key issues for design of suspension bridges in general, and the increased challenges of span lengths beyond 3000 meter. In short, the flutter instabilities will be the main challenge as the length of such a structure will possess very low ratios between the torsional and vertical eigenfrequencies, and the solution is to improve the aerodynamic properties of the bridge-deck. It is also identified that the longitudinal dimension of the bridge has a stabilizing effect in regard to flutter. This should be further investigated. Only aspects concerning the bridge-deck and main cables have been looked into.