SSDA 2018 M E R I T
Steelwork lies at the heart of the
London Wall Place development.
It was decided early in the
design process that the optimum
superstructure solution for both buildings
would be steel frames with concrete floors
and concrete cores.
Sharing a two-storey basement, the
buildings rise to 12 storeys (1 London Wall
Place is 55m tall) and 16 storeys (2 London
Wall Place is 75m tall) respectively, with
their steel superstructures laterally stabilised
by a series of reinforced concrete shear walls
that form the main lift and stair cores.
“The scheme’s main challenge was to
provide a solution for the buildings that
could maximise the built floor area, while
responding to the many constraints imposed
by existing site conditions, planning views
and rights of light,” says WSP Director
Stephen Jackson.
“This resulted in a structural form with
heroically long cantilevers, long span transfer
structures and complex geometry to create
the building set-backs at the upper levels.
This could not have been achieved
without the use of steel.”
The largest transfer structure within
1 London Wall Place is 2m-deep and weighs
72t.
At 2 London Wall Place (south elevation)
a 5m-deep mega-truss at level two enables
all 15 floors above it to cantilever by an
impressive 35m, as well as 16m along the
east elevation. The weight of the mega-truss
is almost the same as the weight of the 15
floors above.
The judges say the use of steel has been
instrumental in enabling the two buildings
to cantilever out over the existing road. A 5m
deep mega-truss at level 2, with enormous
steel members passing through it, offers the
opportunity for a highly unusual new dining
space.
The structural design of Thirty
Broadwick offers optimised
lettable floor areas within Soho’s
tight streetscape, and replaces
a tired building with one that reflects the
district’s modern character.
It now offers exemplar West End office
space, with large, flexible floorplates, that
meet the client’s exacting sustainability
standards. The upper floors step back,
creating large outdoor terraces which
provide valuable amenity space.
The superstructure is a steel frame,
based around a concrete core with cellular
beams allowing for integration of services.
The structure’s frame repeatedly steps
back at upper floors and this has been
achieved by using in excess of 30 fabricated
transfer beams.
“With this project came all of the
challenges encountered when working
within a busy city centre site. Logistically,
great care and attention had to be given to
negotiating the steelwork deliveries into
site, as well as locating a 200t mobile crane
on Broadwick Street to hoist in the 14t
plate girder transfer members,” explains
Severfield Project Director Adrian McCoy.
The site originally had three different
buildings that had been combined to create
one office building resulting in various
levels, misaligned spaces and spatial
inefficiencies.
Building tight against neighbouring
party walls ensured that the new building
maximised floor area.
In summary, the judges say a deceptively
simple project where structural steel
is showcased as the ‘go to’ system for
maximising the development potential on
such heavily constrained sites.
34 NSC
October 18
1 & 2 London Wall Place
FACT FILE
Architect: make
Structural engineer: WSP UK Ltd
Steelwork contractor: William Hare
Main contractor: Multiplex Construction Europe
Client: London Wall Place Limited Partnership
Thirty
Broadwick,
London
FACT FILE
Architect:
Emrys Architects
Structural
engineer:
Heyne Tillett Steel
Steelwork
contractor:
Severfield
Main contractor:
BAM Construction
Client:
Great Portland
Estates plc
© Andy Stagg Photography
/Composite_construction
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/Sustainability
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/Concept_design#Concrete_or_steel_cores
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/Fabrication#Handling_and_transportation
/Construction#Mobile_cranes
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