56
X1
Category 1: Buildings
Software: Scia Engineer
Project
A new community school along Duurstedelaan in the
suburb of Hoograven in Utrecht will be occupied halfway
through 2013. The plan, designed by VVKH architecten,
offers space to three schools (the Ariëns School, the
Da Costa School and De Hoge Raven), as well as
out-of-school care facilities and a ‘sports box’ with two
gym halls.
The three schools and the out-of-school care facilities
are individual free-standing buildings that surround a
sports box. This sports box has been designed as a
kind of box on legs above the central entrance area (the
village square) and its particular structure is explained in
this entry in more detail.
Design
Both of the end walls of the sports box project over the
set back fronts of the village square, whereas the end
walls, as the longitudinal sides of the gym halls, must
be floor-bearing. It was therefore obvious that these
end walls had to be implemented in a façade-high steel
lattice girder (with the span of more than 21 m), in which
the lattice girder also bends around the corner thus
creating the verge.
The upper floor of the gym hall has a clear span of
approximately 12.5 m and is made up of a hollow-core
beam floor 320 mm thick and a structural compression
layer of 60 mm. Because of the restricted height, for
the inside of the sports box the choice was made for
integrated steel Top Hat Q (THQ) beams, supported
by Ø219.1 mm round steel pipe columns. At the
positioning of a single internal bearing line with a span
of approximately 10 m, a floor-to-ceiling steel lattice
girder was also applied, onto which the 1st floor has
been suspended using a suspension column.
The roof comprises a steel structure with perforated
profiled steel roof sheets. The stability is guaranteed by
a number of wind bracings with columns placed at an
angle.
Subsequent to the call for tender and at the request
of the building contractor, the method of construction
was changed from steel to prefab concrete, in which
the floor-to-ceiling steel lattice girders of the sports
box were altered to be constituted prefab concrete
wall beams. In addition, the integrated steel THQ
beams on the steel columns, at the place of the four
internal bearing lines, had to be replaced with prefab
concrete wall beams with various large openings. For
this purpose, these walls have been subdivided and
connected to each other by means of ridge and joggle
pieces so that they can transfer the load from the upper-
level floors to the steel columns. The lintels above the
various openings ensured an adequate coherence.
Construction
For the first design of the sports box in steel, use was
made of Scia Engineer to produce a 3D calculation
model in order to obtain a sound perception about
the transfer of force. To achieve this, all the data of
the vertical and horizontal loads on the structure were
entered into the model. When the transition was made
to prefab concrete, the same calculation model was
used to determine the greater column forces because of
its increased own weight.
The individual prefab concrete wall beams were then
calculated as a 2D slab in which the reinforcement was
determined on the basis of the sectional forces.
New Community “Brede” School - Utrecht, The Netherlands
