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The urban
development of the European cities has changed in the last decade. Investors
now want to build prestigious high-rise building complexes. The horizontal and vertical
reach is much greater than the older buildings. At the same time, these
buildings cause traffic air pollutant. Cars also need space for parking. Because of lack of space garages are built underground
The described development causes
a change in the urban climate and the wind comfort is affected. So can throw
turbulence relevant derogation’s appear, which can restrict the use of the
buildings and the road spaces in the extremely cases.
The high-rise building changes
the wind field in the city area and the urban canopy layer growth. This has a
worse effect on the atmospheric transport in the city, as it can accumulate the
urban/traffic pollutant. This effect is intensified by the traffic.
Underground garages are an
additional problem, especially the ventilation of the garages. If the
ventilation is in the near of the ground, we have a relevant air pollution.
Sometimes we have exceeded the limit values.
For building complexes with a
horizontal range from more than 50 meters or a height from more than 60 meters
a wind comfort study should be made. This studies whether the turbulence in the
nearness is dangerous or not, and whether the people can use the street and
places. On the other hand in the ideal
case the effect of the building of the urban climate will be investigated.
The air pollution of additional
traffic, including the underground garages, must also be investigated. This
investigation is necessary for underground garages with more than 100 places,
if the ventilation near the ground. Ventilation over the housetop implies no
problems.
For the investigation numerical
and physical models can be used.
The numbers in this paper are
only experience values. In other local or regional areas or special cases
(sensitivity of area, back ground values etc.) this values can be higher or
lower.
Examples and further reading
Oke, T. R. (2001): Boundary
layer climates. - 2. ed., repr.
VDI 2053 Bl. 1 (1995): Air
Treatment Systems for Garages and Tunnels Garages, VDI Düsseldorf
Zenger A.
(2000): Modell zur Prognose der Emission und mittleren Luftqualität in
Tiefgaragen sowie Verifizierung anhand von Messungen
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