on the dynamic response of long

ON THE DYNAMIC RESPONSE OF LONG-SPAN
SUSPENSION BRIDGES
ANTONIO CAPSONI1
ANDREA GUERRIERI1,2 , RAFFAELE ARDITO2
1
DEPT. OF ARCHITECTURE, BUILT ENVIRONMENT AND CONSTRUCTION ENGINEERING
POLITECNICO DI MILANO
2 DEPT. OF CIVIL AND ENVIRONMENTAL ENGINEERING
POLITECNICO DI MILANO
PIAZZA LEONARDO DA VINCI 32, MILAN, ITALY
Abstract. The occurrence of internal resonance phenomena has been recently identified as a
potential contributory cause in the appearance of critical dynamic states in long-span suspension
bridges sensitive to aeroelastic phenomena.
In this contribution, which summarizes on going researches, a non-linear dynamic model of a
suspension bridge is devised, with the aim of providing a first attempt toward a unified framework
for the study of aeroelastic and internal resonance instabilities. The analyses is based on a linearized formulation able to capture non-linear structural effects and the linear coupling given by
aerodynamic forces.
Preliminary results confirm that the interaction between aeroelastic effects and non-linear internal resonance can lead to unstable conditions for wind speed levels far lower than those provided
by a classical aero-elastic behavior (flutter analysis).
E-mail address: [email protected]
1