Nonlinear response analysis of long-span bridges under turbulent winds

This paper presents a time domain analysis framework for predicting nonlinear response of long-span bridges under turbulent winds. The nonlinear unsteady aerodynamic forces are modeled based on static force coefficients, flutter derivatives, admittance functions, and their spanwise correlations at varying angles of incidence. This analysis framework incorporates frequency dependent parameters of unsteady aerodynamic forces by utilizing a rational function approximation technique. A comparison with conventional linear approach is made through response analysis of a long-span suspension bridge. The effects of turbulence on the flutter instability are also addressed.