84
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Category 1: Buildings
Project Description
The project centres on a two-storey summer house,
located in the professors’ quarter of the Aristotle
University of Thessaloniki in Vourvourou, Halkidiki,
Greece. The house is built on a hill right at the sea
front, in the middle of a pine forest, and just a few steps
from an almost-private magnificent beach.
The structural members consist of reinforced concrete.
The vertical elements are walls and circular columns.
The plates are rigid, having an area of about 180 m
2
and a thickness of 28 cm. The roof is inclined, while
the middle plate is expanded as a cantilever outside
the perimeter, creating the balconies and the external
passageways. The mat foundation serves as the
ground floor slab, with concrete walls along the
longitudinal direction. Two secondary structures are
attached to the main building; a pergola composed of
concrete beams and a small underground warehouse
(about 50 m
2
).
Basic characteristics
The house has been built in an area with a high risk of
substantial seismic activity. The strongest earthquake
of the 20th century in the area was Ierissos earthquake
in 1932, which had a magnitude of 7.0 on the Richter
scale. On the other hand, the architectural concept
demanded few columns, with the minimal dimensions
possible, and no beams at all, so that the wonderful
view could be enjoyed unhindered. Only some
concrete walls were allowed, mainly in the middle and
the rear side of the house. This type of construction
is very common in non-seismic areas, but it is not
recommended in general for areas with high seismicity,
mainly because of the difficulty of having a credible
calculation model for the transfer of the shearing forces
directly from the plate to the concrete walls.
Using Scia Engineer & ECTools for modelling and
structural design
The structure was modelled with Scia Engineer as a
whole, including the surface elements (plates, walls,
foundation, etc.) and the linear elements (mainly the
columns). The foundation plate is considered to be
supported on the elastic ground through unilateral
contact conditions, in order to deal with the soil
structure interaction.
For the design of the structural elements of the
building, including the EC8 general checks (second
order effects, seismic joint width, infills, torsional
sensitivity, the exception of joint capacity design etc.)
ECtools software was used. ECtools has the ability
to distinguish complex wall sections (cores) and treat
them as one section, recognising automatically the
vertical walls that have been entered on Scia as 2D
surface elements, and designing them as seismic walls,
as required by EC8.
Shear punching on the plates and the foundation was
resolved with the appropriate Scia algorithm which
recognises the position of the column (inside, in the
perimeter or in the corner position), and the possible
existence of holes in the vicinity. The underground
structure was modelled using 2D surface elements as
well.
Conclusion
Although the presented building is rather small in size,
the overall configuration of the structural members
required the use of Finite Elements, in order to build a
reliable model. Although this type of analysis is usually
a laborious and complicated task, Scia Engineer, being
a next generation program, brings the Finite Element
technology to a level of convenience that allows the
engineer to use it in all cases with the minimum effort,
namely in cases ranging from simple conventional
buildings to advanced cases with complex geometry,
non-linear analyses etc.
Software: Scia Engineer
Summer House - Vourvourou-Halkidiki, Greece
