VSH Turòa nad Bodvou - Nemetschek Scia

Project: Bridge ‘Olsene’ across the ‘ Leie’ river
Type: Arched bridge (Bowstring)
Location: River “de Leie”, Dentergem (Oeselgem), Belgium
Owner: Ministerie van de Vlaamse Gemeenschap - Afdeling Wegen
en Verkeer West-Vlaanderen
Architect: Ministerie van de Vlaamse Gemeenschap - Afdeling
metaalstructuren, Brussels, Belgium
Engineering office: Ingenieursbureau Stendess N.V., Lovendegem,
Belgium
Contractor: Steel: Victor Buyck Steel Construction N.V., Eeklo,
Belgium - Concrete: Depret N.V., Zeebrugge, Belgium
Total steel weight: ± 1.000 tons
Total length: 112 m; Span: 110 m
Highest point: ± 20 m (top of arches)
Building period: 2005-2006
Short description of the project
The existing concrete bridge had to be replaced by a new bridge
and this for two reasons.
Firstly, the stability of the existing bridge was no longer guaranteed
for the increased traffic intensity.
Secondly, the free passing under the existing bridge was limited in
height and width and too small for the current ships to pass.
The new bridge is a steel bridge with a span of 110 m, consisting of
2 drive lanes of 4 m and 2 lanes for pedestrians of 2,5 m. The bridge
is an arched bridge (bowstring) with inclined arches of which the
cross sections vary as well in height as in width along the bridge
span. For the bridge deck an orthotropic steel deck with longitudinal
trapezoidal stiffeners was chosen. The bridge is different from
a classic bowstring bridge because the suspensions of the deck at
the arch are not connected to the main deck beams. The suspensions
are connected at the transverse beams, which support the
main deck beams. The whole bridge was completely preassembled
in the workshop, so that the assembly on the spot could be done
smoothly.
The erection, which was studied by Victor Buyck Steel Construction,
was done using a ponton to support the bridge deck temporarily.
In this work of art the great characters of steel came clearly to their
right: the slim line and the playful form of the construction, speed
of assembly and the possibility to combine heavy duty loads with
an architectural design.
Use of ESA-Prima Win and SCIA•ESA PT
Description of technical questions to be solved with
ESA-Prima Win and SCIA•ESA PT
As well for the dimensioning of the steel bridge as for the dimensioning
of the foundations (group of piles) ESA-Prima Win and
SCIA•ESA PT were used.
The complete 3D-model was formed with bars; the orthographic
deck was put together as 2D-elements, with the purpose of creating
the real vertical and lateral stiffness of the bridge. The tension bars,
which support the deck, were simulated as classic bars.
To simulate the horizontal (longitudinal) stiffness of the bridge
supports, a 3D-model was made in which the 3D-bridge structure
and the foundations (group of piles) were combined.
For the calculations with regard to the traffic situation, each bridge
member was given a buckling factor based on the rules of EC3. The
beam check was then made by EC3 steel check of ESA-Prima Win.
The buckling control of the arches was done in three ways. The
first method with EC3-steel check of ESA-Prima Win, the second
method was based on the calculation of the axial critical buckling
force according EC3, the third method used the stability check and
the second order calculation based on EC 3 of ESA-Prima Win. The
second order calculation was done with SCIA•ESA PT. SCIA•ESA PT
gives the possibility of a second order calculation with a predeformation
based on a stability calculation for a 3D-model with bars
and plates. Here SCIA•ESA PT really proved its progress compared
to ESA-Prima win.
In the calculation of this project the use of ESA-Prima Win was
very intense and diverse:
• Combination of 1D-elements and 2D-elements in one
3D-model.
• Combination of different materials in one model (steel bridge
– concrete pile foundation)
• Stability control / critical buckling factor
• Second order calculation based on predeformations from
stability calculations and on EC.
• Use of graphical sections
• Use of cross sections with variable height
• Rib calculations
• Free loads on 2D-model (orthotropic deck)
Description of our experience with ESA-Prima Win and
SCIA•ESA PT when realizing the project.
The challenge in the calculations of the project was found in the
different aspects of steel calculation and in the design of an architectural
bridge for heavy loads.
For this ESA-Prima Win and SCIA•ESA PT were the most suited
software because of the variety of possibilities to check the structure
to the limit, based on linear calculations, EC 3 steel check
control, stability control and second order calculation in one software
program. This could be done in a user friendly and structured
software environment.
Used modules:
• Base
• 3D frame
• 3D shell
• Stability frame
• Second order calculation
Bridge ‘Olsene’ across the ‘Leie’ river
• Steel code check (EC3)
• Rib calculation
• Graphical sections
• Cross sections with variable height
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