Fig. 16 Vertical acceleration time series of the TMD Fig. 15

8|
Szabó et al.
Period. Polytech. Civ. Eng.
the FEM model. The calculated and measured damping 
values were close together. The aerodynamic parameters 
were simulated by using CFD code. The RMS of the alter-
nating lift coefficient and the Strouhal-number were deter-
mined by using the k-ε turbulence model. The vortex shed-
ding phenomenon could be well captured. The simulations 
were performed at high and low turbulence intensities. 
At low turbulence intensity, the more sophisticated 
DDES model was also used. The applicability of the sim-
ple k-ε model was justified based on the comparison of the 
results. The wind velocity magnitude and direction during 
the longest cantilever stage were not favorable as to study 
vortex induced vibrations; the cantilever with free end 
flow conditions and the skew wind together made simpli-
fications necessary to make, which is assumed to be the 
primary reason to the rather conservative results. In order 
to unveil the reasons of the remarkable differences expe-
rienced in the VIV amplitudes, the three-dimensional 
nature of the Komárom Bridge at construction stage is 
planned to be studied by using full aero-elastic FSI (fluid- 
structure interaction) simulation that has been already uti-
lized by the authors for flutter problems. The more sophis-
ticated DES or LES models seem more suitable to be com-
bined with realistic turbulent inflow conditions. Since 
the bridge structure is equipped with monitoring system 
that continuously logs wind flow and bridge deck vibra-
tion data, further detailed validation of our numerical 
approaches can be done in case of VIV occurrence of the 
completed structure.

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