Healthcare
on the Orkney Islands presented main
contractor Robertson Major Projects with
a unique set of challenges. To solve these, it took
into account the remoteness of the island, supply
chain logistics, local landscape, and challenging
climatic conditions.
For example, procuring and shipping
construction materials, such as steel, to the island
and storing on-site well in advance of programme
requirements reduced the vulnerability of the
project to extreme weather conditions.
Steelwork’s speed of construction was also
vital as the envelope of the building is designed
to take into account the available trades on
the islands and to achieve an early wind and
watertight position, thereby allowing internal
trades to progress despite inclement weather.
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Delivering a major healthcare project
Annual Review
Steel works
“The plan geometry of the design is very
complicated and the curved longitudinal
grids are based on a number of different radii.
We’ve used straight steel beams for most
areas, effectively faceting the frame between
grids, although for the tightest curves we’ve
used curved steel members,” says AECOM
Project Engineer Chris Denton.
Utilising steelwork supporting metal
decking has also made it easier to form the
required curves in the floorplate.
“Metal decking is fairly easy to cut on-site
compared to the alternative precast flooring
solution, which would have been far more
challenging and time-consuming,” says
Mr Dalziel.
Predominantly the steelwork is based
around a fairly regular 6m grid pattern, at
least as far as the perimeter columns are
concerned. However, internal columns
arranged around the tighter curves of the
courtyards have been adjusted accordingly,
presenting the scheme with a grid pattern
that can also vary from 4m up to 7m
spacings.
“There may be three columns positioned
along the outside perimeter of a curved area,
but the inside of the curve only requires two
columns,” explains Mr Denton.
The hospital’s configuration is fairly
standard throughout with a central corridor
running down the middle of most parts of the
building, separating rooms on either side. The
corridors are where the services are located
just below the steel first floor and roof beams.
As hospitals are heavily serviced, and this
one is no different, some services have had to
be accommodated within the beam’s depth,
via a series of bespoke holes.
“In some areas, we would have had severe
congestion without running some services
through the beams,” says Mr Dalziel. “Having
a BIM model to share with the steelwork
contractor BHC and all of the other team
members meant that we could avoid clashes
and provide sufficient room for services.”
The entrance to the hospital is
accommodated within a large central
column-free space known as the hub. This
double-height space will have a series of
north lights positioned within the roof,
allowing plenty of natural light into the hub.
The hub is formed with a series of
15m-long rafters creating the required
spacious zone.
From the hub the southern courtyard can
be accessed. This totally enclosed outdoor
area will be landscaped and feature a sensory
garden and seating to create a sheltered area
for visitors and patients alike. The other
partially enclosed courtyard will be an
outdoor area for a range of users.
The building’s steel frame derives most of
its stability from vertical diagonal bracing,
positioned in internal partition walls and
perimeter areas where there are no windows.
This has worked well for the ground
floor where the GP practices, dentistry,
outpatients, staff areas and kitchens are
located.
The first floor, which predominantly has
operating theatres and patient rooms – all
en-suite single occupancy units – has been
designed with more flexibility in mind.
Stability to the steel frame on some parts
of the upper floor is therefore provided by
moment frames.
Using moment frames instead of bracing
has allowed the scheme the flexibility to
change partition walls and room layouts
right up to the last minute, without
causing any undue issues to the steelwork
contractor’s fabrication programme.
Summing up, NHS Orkney Chief
Executive Cathie Cowan says: “This
development will match our aspirations to
deliver the highest quality care and services
from fit-for-purpose facilities.”
A combination of
faceted straight
members and curved
beams form the
courtyards