SSDA 2017
NSC 9
Annual Review
Commonly referred to as the
Cheesegrater, The Leadenhall
Building was designed as a wedgeshaped
structure in order to meet
the client’s aspiration for an outstanding City
of London landmark tower.
Part of its unique design are the panoramic
lifts which have been placed on the vertical
north elevation, so they can serve all the
office levels. As a result, there is no central
core, and stability is provided by a perimeter
braced steel mega-frame, placed outside of
the building envelope.
The steel design is said to allow the floors
to be exceptionally open, with views in every
direction and spans of up to 16m. There are
no more than six internal columns within
floor plates of up to 43m × 48m.
“The use of steel is fundamental to the
value of this building. It is visibly integrated
into the architecture to an extent that is
highly unusual for a skyscraper, creating a
powerful tectonic quality,” says Arup Director
Nigel Annereau.
The most striking example of this is in
the mega-frame bracing system. It is formed
with vertical columns, positioned where they
are most needed, on the east, west and north
faces, and a diagrid structure on the more
lightly-loaded south face.
Summing up, the judges say this project
had a committed client, architectural and
engineering excellence, fabrication precision
and construction ingenuity and innovation.
This world-class project is an exemplar for
large commercial buildings.
The T-Pylon was a design
competition winner in 2011 and
has been designed to carry 2 ×
400kV, but can be modified to
alternative specifications.
The competition was a response
to a global wave of public opposition
towards conventional lattice towers, to
find an alternative that would be a visual
improvement to current solutions as well
as cost-efficient and functionally superior.
The idea was that the new design would also
signal the transition into renewables.
The T-Pylon is made from steel, which
has allowed for unique geometries. Contrary
to conventional lattice tower designs, the
arms of the T-Pylon are slightly raised,
which give the pylon a more optimistic and
positive appearance. The few parts making
up the pylon have been welded together and
subsequently painted white.
The tower design is shorter and leaner
than traditional lattice towers for better
aesthetics, less environmental impact, and a
shorter installation process.
Nationalgrid former Executive Director
Nick Winser says: “In the T-Pylon we have
a design that has the potential to be a real
improvement on the steel lattice tower. It’s
shorter, lighter and the simplicity of the
design means it would fit into the landscape
more easily. In addition, the design of the
electrical components is genuinely innovative
and exciting.”
The use of steel and the alternative design
has made it possible to obtain the aesthetic
and functional goal: to minimise the visual
impact on the surrounding landscape,
while also providing a resistant and durable
solution.
“The T-Pylon blends better into its
surroundings as it is shorter and sleeker than
the conventional lattice pylon. The modern
design is fit for the 21st Century and beyond,”
says Bystrup Business Development Manager
Mette Mikkelsen.
In summary, the judges say the T-Pylon
represents a generational step change in
power transmission hardware. This is a
steelwork design classic.
FACT FILE
The Leadenhall
Building, London
Architect: Rogers Stirk
Harbour + Partners
Structural engineer:
Ove Arup & Partners
Ltd
Steelwork contractor:
Severfield
Main contractor:
Laing O’Rourke
Client: C C Land
FACT FILE
T-Pylon
Architect: Bystrup
Structural engineer:
Bystrup
Main contractor:
Balfour Beatty Power
Transmission &
Distribution
Client: Nationalgrid UK
The Leadenhall Building, London
T-Pylon
© Paul Carstairs/Arup
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