Environmental Engineering Reference
In-Depth Information
One of the tallest hybrid towers built so far is the one erected by the Dutch company
Mecal on the wind power test site at Grevenbroich near Cologne. The hub height of this
2.3 MW turbine is 133m. With a rotor diameter of 93m, that makes the total height
about 180m. The tower foundation is 30m in diameter and is founded on vibrated stone
columns that extend 14m into the subsoil.
The tower design above this consists of 40 precast concrete elements finished off
at the top with an adapter in the form of a single segment. In cross-section, the tower
is divided into eight parts: four quarter-circle elements and four straight elements
that
taper towards the top. It
is this design that gives the tower its striking
conical form.
Vertically, the tower is subdivided into five levels each 15m high (Figure 5.8).
Transporting and erecting these precast concrete elements presented a challenge in
terms of the logistics. Two powerful mobile cranes were needed on site.
Filled mortar joints are used horizontally, whereas the vertical joints are in the form of
keyed and reinforced concrete-filled pockets.
The individual phases of the erection of the adapter segment are shown in Figure 5.9.
Precision work at a height of 75m was necessary here in order to fit the threaded bars
into the top of the tower. But the prevailing wind conditions allowed this work to be
completed in just 15minutes.
Fig. 5.8 Erecting the 4th level,
from 45 to 60m. (source: ATS Advanced Tower Systems,
Enschede, NL)
Search WWH ::




Custom Search