Fig. 4 Structural beam-truss model of the bridge at construction stage Fig. 5

4|
Szabó et al.
Period. Polytech. Civ. Eng.
natural frequency and the damping values are in good 
agreement. The applicability of TMD during construction 
stages was also proved, which is practically meaningful.
4 Aerodynamics of the bridge deck
The aerodynamic parameters were simulated by utilizing 
open-source code OpenFOAM (version 9). The Komárom 
Bridge deck section was considered both at construction 
stage and after competition with the additional elements, 
such as the asphalt layer, curbs and handrails installed. 
The computational domain used in the two-dimensional 
simulations can be seen in Fig. 8. The domain sizes were 
determined based on recommendations found in literature 
in order to keep blockage ratio low.
In Reynolds-averaged models (RANS), the Navier-
Stokes equation together with the continuity equation are 
averaged over time (denoted with overbar), resulting in 
averaged equations according to Eqs. (3) and (4).

 
 
   
 
t i
j j i
i
j j i
j i j
u u u
p
u
u u
1


' '
(3)


i i
u 0
(4)
The averaging leads to new unknowns (
u u
i j
' '
), which are 
referred to as the Reynolds-stresses due to velocity fluctua-
tions. In order to close the equations, turbulence models are 
needed to introduce. The widely used k–ε equation turbu-
lence model was selected due to its simplicity and low com-
putational demand. Despite the fact, that vortex shedding 
problem can best be handled by the computationally more 
costly turbulence models, e.g., LES, k–ε model can still 
be used for fully developed turbulence around bluff bod-
ies [8]. Unsteady simulations were used in accordance with 
the unsteady nature of the vortex shedding phenomenon. 

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