Frequency Response of Suspension Bridges Installed on Complex Topographies and Subjected to Wind Turbulence

Today, it is becoming natural to observe highly turbulent winds of a stochastic nature, which in no way respect the protocols taken into account for the deterministic dimensioning of suspension bridge structures. On the basis of the above, it is necessary to adapt infrastructure design to the problems associated with climate change, such as random wind gusts, hurricanes and storms. In this paper, we investigate the frequency-domain aerodynamic response of the Hardanger suspension bridge in Norway, installed on a complex topography and subjected to wind turbulence, by describing the aerodynamic wind phenomena surrounding the bridge deck and the aerodynamic force field according to stochastic wind theory. A formulation that takes into account the lateral, vertical and torsional movements of the bridge deck structure has been used. The frequency description is used to evaluate the response of the bridge to buffeting and compare it with literature results, based on the standard deviation and power spectral density of measurement recordings at the bridge site. The effects of angle of attack, turbulence power spectrum and aerodynamic admittance function on the buffeting response of the treated bridge are evaluated. Next, parametric studies were carried out to clarify further concepts in the buffeting analysis of long-span suspension bridges. Finally, global considerations were examined to establish standards for further analysis.