Time Domain Flutter and Buffeting Response Analysis of Bridges

Numerical simulation of wind effects: A probabilistic perspective

“…This reduced-order representation, of course, must warrant that the important characteristics of the random field and related quantities remain unchanged, or the modification resulting from the approximate representation is acceptable. Several studies on the covariance matrix-based POD technique have demonstrated that truncating higher wind loading modes helps to expedite computations of global wind loads and their effects, e.g., Tamura et al 1999;Chen and Kareem 2000. However, truncation of higher modes may not work effectively in the case of local response, which may lead to an underestimation of the local wind loads and their effects (Chen and Kareem 2005).…”

“…The flutter analysis is generally conducted by complex eigenvalue analysis, whereas the buffeting response analysis is typically handled using a mode-by-mode approach that ignores the aerodynamic coupling among modes. More recently a coupled multi-mode flutter analysis framework has been introduced (Chen et al 2000). This has led to a convenient transformation of the equations into a frequency independent state-space format.…”

“…Traditional analysis approaches are not suitable for accommodating these computational challenges. To include nonlinearities of structural and aerodynamic origins, the time domain approach is more appropriate (e.g., Chen et al 2000 and the references cited). Most of the studies concerning the buffeting response have used the quasi-steady theory for modeling the aerodynamic forces, thus ignoring the frequency dependent characteristics of unsteady aerodynamic forces in the numerical scheme, potentially impacting the accuracy of the response estimates.…”

New frontiers in aerodynamic tailoring of long span bridges: an advanced analysis framework

“…In fact, these unsteady force characteristics can be described in terms of impulse response functions in the time domain. The time histories of unsteady aerodynamic forces can be calculated using convolution integrals involving the impulse response functions and structural motions or wind fluctuations (e.g., [14,17]). …”

“…By comparing bridge flutter with airfoil flutter, Selberg [2] suggested an empirical formulation for estimating the bridge flutter onset velocity. The pioneering work of Davenport [3] and Scanlan [4,5], among others, concerning bridge buffeting and flutter have led to a number of analytical developments in bridge aerodynamics/aeroelasticity using realistic aerodynamic force modeling of bridges with bluff sections under turbulent winds (e.g., [6][7][8][9][10][11][12][13][14]). With these developments as a background, this paper highlights the state-of-the-art developments in the aeroelastic analysis and identifies new frontiers in aerodynamic tailoring of long span bridges.…”