precast cores were chosen for their speed
of installation, but they offer no structural
stability to the main frame steelwork, as this
is all derived from cross bracings located at
either end of the car park and in between the
internal line of columns.
Delivering the steel to the site was a fairly
routine procedure as the surrounding roads
are wide enough for most trucks and the
site initially had plenty of laydown space.
However, many pieces of steelwork had to
go on one more journey than they would
ordinarily expect.
All of the project’s steel has been hot-dip
galvanized, a process which was necessary
because of the atmospheric environment that
can be expected due to the site’s proximity to
the River Mersey estuary.
“Ordinarily, the 16m-long beams would
have been delivered to site after they’d been
galvanized. However, we had to return
them to our fabrication yard in order to
cut holes in them to accommodate the car
park’s sprinklers. This work couldn’t have
been done prior to galvanizing as it would
have damaged the steelwork,’ explains Leach
Structural Steelwork Quantity Surveyor
Patrick Rostron.
Aside from the main beams, the largest
single elements in the car park are a series of
trusses that form two large openings along
the ground floor level, one for vehicle access
and the other for exiting.
As ground floor columns had to be
omitted to form these spaces, 15m-long ×
3m-high transfer trusses were installed to
form a bridge at first floor level and support
the reinstated columns lines for the floors
above.
The trusses were brought to site in
individual sections, with each member
installed during the erection programme.
This proved to be a time-consuming process,
especially as the trusses’ internal members
are connected via gusset plates, some of
which have up to 48 bolts.
This led the project team to change one of
the trusses to a 1.8m-deep plate girder as this
was quicker to install.
The steelwork will be left exposed and in
full view within the completed structure,
while from the outside, the frame will be
visible through the cladding.
Summing up, LeachRhodesWalker
Architects Managing Director Christian
Gilham explains: “This is an engineering
structure and so it was important to have the
steelwork as a feature, which can be glimpsed
through punched holes in the aluminium
cladding.
“With reference to Liverpool’s maritime
heritage, the cladding is also adorned with
Schooner motifs, while other areas of the
structure are clad with red/brown brickwork,
which is a further nod to the city’s industrial
past and the area’s surviving warehouses.”
NSC 21
Apr 20
DOCK, LIVERPOOL : CGI VIEW 01
Drawn By: MJ Date: 21.12.18 Dwg No: 7829_L00_94A
Car park
“We looked at all framing
solutions, but went for a
steel-framed option with metal
decked floors and precast cores
as it was the most cost-effective
method for this project.” Visualisation of how
the completed car park
will look
Steelwork erection
nears completion.
Large trusses form the
access and exit points
on the ground floor.
The car park's cladding
has motifs that are a
reference to the city's
maritime history
/Concept_design#Structural_options_for_stability
/Braced_frames#Vertical_bracing
/Corrosion_of_structural_steel#Atmospheric_pollution
/Metallic_coatings#Hot-dip_galvanizing
/Sprinklers_in_UK_fire_codes
/Trusses
/Construction#Steel_erection
/Steel_construction_products#Plate_girders
/Building_envelopes