SSDA 2019 M E R I T
NSC
October 19
The G. W. Annenberg Performing
Arts Centre is a new theatre at
Wellington College, one of the
UK’s leading independent schools.
Seating 900, and with a total capacity (in
College Assembly mode) for 1,200 people, it
is said to be a unique circular theatre, built
into a gently sloping site.
Linking the new theatre with the existing
Christopher Lee Theatre in a clear, columnfree
span is the Cultural Living Room (CLR).
Besides forming the main foyer to the
theatre, this space has been created to
provide an open public space for ad-hoc
performances and the display of arts and
crafts produced by the college students.
Inside the theatre, the 33m-diameter
roof spans over the auditorium where the
curved plan of the building is said to fully
complement the internal arrangement of
seating and structure around the focus of
the stage.
High-level walkways within the roof
not only give access to the lighting galleries,
but also form the backbone of the roof
support structure, formed by a rectilinear
arrangement of cambered Warren/
Vierendeel hybrid trusses.
Designing a round building with a heavy
roof (for acoustic reasons), yet which still
has a clear span presented problems for both
the design and construction teams.
The solution PBA designed transferred
the vertical loads of the roof and external
walls back into the building through the
balcony support structure, then to the
ground through lower level columns hidden
within the various internal ground floor
walls.
The structure also faced complications
adjacent to the CLR where there were no
internal columns, to allow for efficient
circulation. This was accommodated
through the introduction of a storey deep
back-spanning cantilever curved truss,
laterally restrained by the first-floor slab and
angled balcony structure.
Innovative and extensive structural
transfer systems were developed throughout
to enable the architect’s vision for this
complex building. However, the overall
complexity did not translate into complex
steel fabrication details, as the building
was designed to be a collection of simpler
structures. This was achieved in part by
keeping the perimeter column spacing and
internal floor spans to a minimum, thereby
reducing the overall load applied to each
transfer beam.
According to PBA Senior Engineer Gwyn
Owen, steel was the only viable material
that could be used to form the theatre, the
design of which was highly constrained
by its large roof spans, high loads, limited
structural zones and extensive ventilation
requirements.
In summary, the judges say this quietly
assured and successful project is a credit
to all involved. Resolution of the circular
building form with the functional and
acoustic requirements of the auditorium
was impressive. The engineer and steelwork
contractor have rationalised the project into
a very economic steel solution, enabling the
architectural intent to be realised.
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FACT FILE
Architect: Studio Seilern Architects
Structural engineer: PBA now part of Stantec
Steelwork contractor:
Advanced Fabrications Poyle Ltd
Main contractor: Beard Construction
Client: Wellington College
G W Annenburg Performing
Arts Centre
Forming the heart of a new cultural quarter of a
prestigious college, a new circular-shaped theatre
has been built into a sloping site in order to blend
into its natural surroundings.
/Leisure_buildings#Theatres_and_auditoria
/Leisure_buildings#Theatres_and_auditoria
/Trusses#Warren_truss
/Trusses#Vierendeel_trusses
/Trusses
/Fabrication
/Design
/Leisure_buildings#Cost_efficient_design