A new numerical approach to reproduce bridge aerodynamic non-linearities in time domain

A new approach to deal with aerodynamic non-linearities in time domain has been developed using a rheological mechanical model. The parameters of the rheological model have been estimated from specific wind tunnel tests. Once identified, the rheological system allows to reproduce the aerodynamic forces, starting from the bridge motion and the wind velocity components and to take into account the dependence on the reduced velocity and the non-linearities due to the large changes in the angle of attack induced by turbulence and the amplitude of motion.