Time domain vs. frequency domain characterization of aeroelastic forces for bridge deck sections

Application of random eigenvalue analysis to assess bridge flutter probability

“…This can be accomplished for instance by replacing the quantity U with the quantity U[1þ w(t)] with w(t) a random noise (Bucher and Lin, 1988;Sarkar and Tsiatas, 2009). Nevertheless, the use of such a parametric disturbance has been noted as not being fully representative of the physical phenomenon (Caracoglia, 2011) and that the effect of turbulence on flutter should be considered either through a loss of spanwise correlation of the aeroelastic loading (Scanlan, 1997) or by propagating through the system a parametric-type disturbance in the spanwise correlation of F b (Caracoglia and Jones, 2003). Another approach (Caracoglia, 2013), which is compatible with the interpretation of the role of aeroelastic forces versus buffeting forces in the "classical" bridge aerodynamics formulation by Scanlan (1997), has also suggested that the role of buffeting force (and perturbation) is usually of secondary importance in comparison with the variability in the coefficients describing the aeroelastic loads.…”

“…The indicial function Φ Mh is described in this study by using 2 terms in the summation (5), see Table 2; additional discussion on Φ Mh will be provided in a later section. Following the method presented in Caracoglia and Jones (2003), the parameters shown in Table 2 are obtained by least-squares fitting of the flutter derivatives with the series of rational fractions corresponding to the general representation (5). The flutter derivatives reconstructed from the indicial functions with the parameters taken from Table 2 (mean values) Table 2 and distributions as described below.…”

Aerodynamic Parameters on a Multisided Cylinder for Fatigue Design

“…Gupta and Sarkar (1996) conducted wind tunnel tests on a circular cylinder to identify vortex-induced response parameters in the time domain. Kareem (2000, 2002) worked on modeling aerodynamic phenomena, buffeting and flutter, in both time and frequency domains, and Scanlan (1984Scanlan ( , 1993, Caracoglia and Jones (2003), Zhang and Brownjohn (2003), and Costa (2007) and Costa and Borri (2006) studied the aerodynamic indicial function for lift and admittance functions for structures. Together this collection of work provides the motivation for the model discussed herein.…”

Recent developments on bridge flutter stability estimation accounting for errors in the aeroelastic loading

“…The "link" between experimental values of the FDs and eqn (2) is based on nonlinear regression of c i,αα , d i,αα , with pre-selected model order m αα [14]. Expressions similar to eqn (2) can be postulated for the IF associated with M AE and a variation in dh/dt (Φ αh (s) with parameters C M * , c i,αh , d i,αh and order m αh ), and for the lift-force IFs, dependent on either a step-variation of α, Φ hα (s) or vertical velocity, Φ hh (s).…”