2|
Szabó et al.
Period. Polytech. Civ. Eng.
calculation of VIV amplitudes is of primary importance.
Simplified closed formulas (e.g., Eurocode, [4]),
section
[5, 6] and full aero-elastic wind tunnel models [7] or fluid-
structure interaction simulations [8] are widely used, but
there are still uncertainties as to the prediction of the VIV
amplitudes [9]. In this paper a slender cable-stayed bridge
at Komárom
was considered, which was equipped with
monitoring sensors during the
most critical construction
period; therefore, precise wind
and vibration data series
were available. The main goal was to validate our numer-
ical (structural and fluid dynamics) models in order to
improve the reliability of the VIV amplitude calculations.
2 The new Komárom Danube Bridge project
The Komárom Danube Bridge is a cable stayed structure
with unusual, one-sided single pylon arrangement, which
is therefore fully fixed at the bottom. The main span
L
is 252 m. The orthotropic deck has trapezoidal ribs and
two I-shaped stiffening girders at both sides. The curved
cross girders are placed at every 3.00 meters. The deck has
a width
B of 20.40 m, and a depth
D of 2.50 m. The stay
cables are composed of
A = 150 mm
2
high-grade strands
(
f
u
= 1860 N/mm
2
) with a strand number of 43, 55 and 85.
The cross section is shown in Fig. 1
with the team of
designers ready to make pedestrian excitation tests at the
end of the deck. Considering the slenderness of the bridge,
6 pieces of tuned mass dampers (TMD) were installed on
the deck in order to mitigate vortex induced vibration.
A single TMD has a moving mass, stiffness and damping
of
M = 5 t,
K = 36.5 kN/m and
C = 3.4 kNs/m, respectively.
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