Gianni Arioli and Filippo Gazzola
Torsional instability in suspension bridges: the Tacoma Narrows Bridge case
(737K, pdf)

ABSTRACT.  All attempts of aeroelastic explanations for the torsional instability of suspension bridges have been somehow criticised and none of them is unanimously 
accepted by the scientific community. We suggest a new nonlinear model for a suspension bridge and we perform numerical experiments with the parameters 
corresponding to the collapsed Tacoma Narrows Bridge. We show that the thresholds of instability are in line with those observed the day of the collapse. 
Our analysis enables us to give a new explanation for the torsional instability, only based on the nonlinear behavior of the structure.