Pudong and Shanghai World
Financial Center
by
Paul Koppen
Pudong
Pudong
used to be namely farmland and countryside until 1990. In
this year the Chinese government decided to set up a
?Special Economic Zone? in the district. The western tip of
the Pudong district was designated to be the new financial
centre of the modern China, called the ?Luijazui Finance and
Trade Zone?. Several landmark buildings were constructed in
this zone during the 90?s to raise the image of the area.
These include the Oriental Pearl TV Tower and the Jin Mao
Building. Even now a lot of buildings are being constructed
in this area. Personally I have never seen so much
skyscrapers being constructed at once. One of these
skyscrapers is the Shanghai World Financial Tower.
Image
1.1: Skyscrapers are popping out of the ground in
Pudong.
Shanghai World Financial Tower
Introduction
The
Shanghai World Financial Tower is a supertall skyscraper
that has been intermittently under construction in Shanghai.
It is a mixed use skyscraper which will consist of office
spaces, hotel rooms, conference rooms, observation decks and
shops on the ground floors. The tower was originally planned
for construction in 1997, but this was temporarily
interrupted by the Asian Financial Crisis in the late 90?s
and later to accommodate the design changes by the developer.
The tower, which has 101 stories, is designed by Kohn
Pederson Fox. The Shanghai World Financial Tower?s height
has been set at 492 meters and this height will be reached
around September 2007. The final completion will be at the
beginning of 2008 and it will temporarily be one of the
tallest skyscrapers in the world.
Image
2.1: The SWFC with the tube-structure which is still
visible.
Construction
The
Shanghai World Financial Tower is a very tall tower from
which the floor plans that are at the lower levels have a
size from 58 meters by 58 meters. There can be concluded
that it is a slim tower and that it is a difficult business
to transfer the lateral forces down to the foundation. In
short, how is there taken care of the stability.
Applying a tube-structure for extreme tall buildings is a
common phenomenon. A tube-structure is in fact a spatial
truss which stands up vertically. It is located at the
fa?ade of the building.
Image
2.2: The structural system of the building
The
vertical columns of the tube-structure are located at the
corners of the building and consist of steel columns which
are afterwards being encased in reinforced concrete.
To
connect the mega columns with each other there were belt
trusses applied. These trusses are made of steel and there
are 7 of these trusses to be found in the building. Not only
does this belt truss have a constructive function, it also
has a safety function. This is in case of an emergency. If
there is a case where the building has to be evacuated, the
people will then get together at the belt truss and then
leave the building. These trusses are as high as one story
and they count as very safe floors. In this way the
construction of the building and the safety of it are
beautifully combined.
The
last elements of the tube-structure are the mega braces.
These are connected with the mega columns and the belt
trusses. They transfer loads that are carried with the mega
columns, belt trusses and other elements of the building to
the entire building. These loads will be divided.
Not
only by applying a tube-structure is the stability of this
building guaranteed, but also by applying a core wall. This
core wall has a size about 30 meters by 30 meters and it
reaches to the 79
th
floor of the building. The
core wall will be constructed with steel encased reinforced
concrete. Pursing the highest grade in safety, the
tube-structure in the Shanghai World Financial Tower will be
connected with the core wall. There are two ways of ensuring
the stability of the building. This system is called the
dual lateral force system and it is ideal for tall buildings
and is designed to be much safer and more robust during
earthquakes and typhoons compared to a single lateral force
system, which resists forces only with perimeter columns and
beams.
The
tube-structure is connected to the core wall with the
outrigger trusses. These outrigger trusses are located at
three different levels in the building. Each outrigger truss
is as high as three stories. At the first two levels where
these outrigger trusses are applied, there are also the sky
lobbies located. These levels are at the 28
th
, 29
th
floor and at the 52
nd
, 53
rd
floor of
the building. The sky lobbies are as high as two stories.
Functionality is beautifully combined with the construction
of the building.
The
reason why the core wall only reaches till the 79
th
level is because the hotel starts here. The hotel needs
another floor plan than the other functions that are located
in the building. And it couldn?t use a core wall in its
floor plan. For this section of the building only the
tube-structure takes care of the stability.
The
section above the hotel is the observatory. The construction
of the last three floors of the hotel, the penthouses, and
the observatory is completely made out of steel. These are
in total 11 floors. The reason because of this is that the
stability of the building is already ensured. The steel
framework is only connected to the stable structure. The use
of steel also works weight reducing and because of the fact
that there are only a few more levels, there isn?t much
pressure to resist by the construction. The choice to make
it out of steel is a logical one. It is also easy to create
the characteristic aperture in steel.
If in
another way constructed it would be a very difficult task.
Image
2.3: The SWFC divided in different sections.
Elevators
In such
a tall building a lot of people have to go up to one of the
many stories. The tower has 91 elevators in total to
transport this large amount of people. If traditional
elevators would have been used, the already small amount of
free floor space would have been even smaller. The floor
plan would mostly consist of a large amount of elevators.
This problem is being solved by stacking two elevator cars.
By doing this, it is possible to transport twice as many
people in one ride with the minimal use of floor space. By
stacking two elevator cars the traveling time is reduced to
a minimum during rush hours, when the amount of people that
need to be transported is at its peak. Stacking two
elevators cars is a system successfully deployed in
skyscrapers around the world.
Image
3.1: Two elevator cars are being stacked to transport the
largest amount of people possible.
Image
3.2: All the different elevators that are in the building.
Please
take notice of the elevators that are at each side of the
characteristic aperture.
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