Nonlinear Aerodynamic and Aeroelastic Analysis of Bridges: Frequency Domain Approach

A frequency domain approach for nonlinear bridge aerodynamics and aeroelasticity, based on the Volterra series expansion, is introduced in this paper. The Volterra frequency-response functions and the associated linear equations are formulated utilizing a topological assemblage scheme and are identified utilizing an existing full-time-domain nonlinear bridge aerodynamics and aeroelasticity analysis framework. A two-dimensional sectional model of a long-span bridge is used to illustrate this approach. The results show a good comparison between the time-domain simulation and the proposed frequency-domain model. The availability of Volterra frequency-response functions enables gaining a qualitative insight into nonlinear bridge aerodynamics and aeroelasticity.