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(rshsdepot) Berlin, Germany
Links:
http://www.stadtentwicklung.berlin.de/verkehr/stadtverkehr/en/bild_fern_061.
shtml
http://www.stadtentwicklung.berlin.de/verkehr/stadtverkehr/en/bild_fern_03.s
html
Expensive Complications Bedevil Ambitious Berlin Station
By Georg Küffner
Frankfurter Allgemeine Zeitung
BERLIN. "A Unique New Building in Berlin."
This was the characteristically self-confident tone with which Deutsche
Bahn, Germany's national railroad operator, announced the mid-June opening
of the east-west rail axis in Berlin. The first trains will be passing
through the new Lehrter Bahnhof station in a few days, though they will not
be traveling south through the "cathedral of the mobile world" for a few
years yet.
The biggest and costliest single project in Deutsche Bahn's history is due
for completion in 2006, after the schedule was accelerated for the next
soccer World Cup, which Germany will host. It remains to be seen whether the
schedule can be met, however, as a series of immense technical challenges
still face the planners. Right before the station, for example, the
subterranean north-south stretch is missing two 80-meter (263-foot)
sections, which are to be "brought up" via the so-called open construction
method used so often before in Berlin.
The method is considered ideal in environmental terms because it does not
touch the groundwater or harm the trees in the Tiergarten park above.
Building has been delayed, however, by a series of uncontrolled intrusions
of water in the swimming pool-sized foundation pits. The unorthodox methods
employed at the Lehrter Bahnhof construction site have also led to delays;
instead of planning followed by approval and then realization, all three
processes are running simultaneously at the new station.
Nor are matters helped by the minimal use of standard techniques. All
constructional details are therefore subjected to a complex inspection
process before final approval by railroad regulators.
The same procedure has also been applied to the glass roof now nearing
completion. As the rail bridges that support the roof are slightly curved
and bulge out at the center of the station, every section of the roof is
different to the next. The roof could not have been built without
computer-aided geometric calculations and computer-controlled cutting
processes for the glass and steel. Yet the Stuttgart-based structural
engineer who designed the construction, Jörg Schlaich, does not consider
this a flaw. On the contrary; he sees his roof as a pioneering example of
modern railroad station design. As huge domes are no longer required to
accommodate steam-spewing locomotives, their place can now be taken by stout
elliptical glass tubes that spread across the tracks like an armadillo's
body.
Modern materials and highly efficient calculation methods, says Mr.
Schlaich, enable constructions whose flow of forces and functionality can
even be appreciated by the technically unversed. Steel cables were employed
to provide tension in the flat, curved safety arches of the roof, for
example, so that they are self-supporting like their parabolic predecessors
in stations built a century ago.
The accelerated schedule and the reduction of the erection time from seven
to four months, however, mean that the roof -- intended as the Lehrter
Bahnhof's most visually distinctive feature -- will now be "only" 290 meters
long instead of the 430 meters originally planned. Mr. Schlaich criticizes
this condensed solution as a "violation of the esthetic concept of the
overall construction," arguing that the elegance of the winding body would
only have been fully realized at full length.
In his eyes, the decisions taken by Deutsche Bahn Chairman Hartmut Mehdorn
can be compared to those of a customer who orders a tailor-made suit and
then, during the final fitting, demands that the sleeves be shortened to the
elbow and the legs to the knee, thereby losing the shape of the suit and
requiring complicated modifications such as new hemlines.
He is equally displeased about the roof of the station, and not just because
of the lost elegance: The construction engineer also complains of an
unnecessary repetition of work -- the roof was originally to have comprised
separate parts and could therefore not simply be cut off at either end. With
the fixed points being shifted for the shortened roof, the whole
construction had to be recalculated. The two outer roof portals were also
rebuilt in order to withstand the stress from the wind now streaming under
the roof. This area now also needed thicker sheets of glass, and because the
forces acting on the rail bridges were altered by the shorter version of the
roof, this in turn required new structural tests.
When the first high-speed ICE trains arrive at the Lehrter Bahnhof, however,
the smaller roof will also attract the attention of travelers with little
interest in architecture -- passengers alighting from the cars at the front
and back of the train will be exposed to the elements. The fact that the
same fate awaits those in the center section of the train is a further
peculiarity of the new station, which Deutsche Bahn boasts of in its
marketing as a "glass temple for travelers." The heart of Lehrter Bahnhof,
the area where the east-west and north-south lines intersect, will remain
roofless for an indefinite period: Construction of the two "bookend
buildings" that span the rail bridges will not actually begin until tenants
have been found for the 50,000 square meters (538,000 square feet) of office
space. Only then can the roof be connected at this point.
But if and when this will happen is currently as uncertain as the question
of what it is to become of the redundant sections of the roof. While Mr.
Schlaich hopes that the Lehrter Bahnhof will eventually get its full
armadillo shape, there is increasing pressure to make an exhibition hall out
of the "surplus" parts.
Meanwhile, public impatience with and criticism of the entire project, last
estimated to have a price tag of euro 3.1 billion ($2.9 billion) appears to
be growing.
Bernie Wagenblast
Transportation Communications Newsletter
http://groups.yahoo.com/group/transport-communications/
=================================
The Railroad Station Historical Society maintains a database of existing
railroad structures at: http://www.rrshs.org
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