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CONSTRUCTION WORLD
AUGUST
2016
PRECAST
Turner & Townsend, appointed by
Bombela Concession Company
(BCC) as project managers, adjudi-
cated Stefanutti Stocks Civils as the
preferred contractor, whereafter BCC awarded
the construction contract to Stefanutti
Stocks. Work on site started in July 2015, and
the completed platform was handed over in
May 2016.
The scope of work undertaken by Stefa-
nutti Stocks Civils included the design and
construction of the entire station extension
and all associated works. This included
the modification of existing infrastructure
to accommodate the new installation; the
installation of precast struts; the manufac-
ture and installation of precast slabs and
balustrade walls; the manufacture and instal-
lation of a new steel roof canopy with fire
escape staircases; and all platform finishes
on completion.
The precast concrete elements included
5 ton struts and 20 ton slabs and balustrade
walls, which were manufactured off-site.
Prior to the installation of these precast
struts and slabs, the existing parapet walls
were saw cut using a diamond rope-and-
blade cutting system.
The project included a number of unique
and interesting aspects, both in terms of
constructability and the technology required
to achieve the necessary construction.
Not only did the entire installation of the
platform extension take place at a height of
18 metres above ground level, it was also the
first time that an upgrade to the Gautrain
station has been undertaken, while train
operations continued as normal.
“Our collaborative brainstorming and
feasibility studies resulted in innovative
ways to execute temporary works,” says Glen
Deyzel, Stefanutti Stocks Civils contracts
manager for the project.
“We had to consider an installation
methodology that would allow us to achieve
our best production and address all safety,
environmental and construction risks.”
Risk considerations included the project
prerequisite that the trains were to remain
operational at all times. Furthermore, the
access road, directly above which construc-
tion took place, also needed to remain
operational at all times, as it was an airport
entry point.
The confined working area as well as
the weight of the precast elements that
were assembled to build the platform
required the use of what is said to be the
largest tower crane in Africa. This crane
was utilised at the platform extension at a
capacity of 26,1 tons at a radius of 40 metres.
This crane has a maximum capacity of
10 tons at a radius of 82,6-metres.
Gautrain platform extended with
PRECAST ELEMENTS
By Chrissi Maria
The Gautrain Station at the OR Tambo International Airport
(ORTIA) has recently been extended by 55 metres in order
to accommodate a further two Gautrain carriages and bring
the station capacity up to a full four-car train set.
“When planning this project we had to
address multiple challenges including our
proximity to people, airport traffic, live trains,
the adjacent hotel – and of course we had to
consider all these when planning access to
do the work,” says Stefanutti Stocks Civils’
contracts director, Mike Stevenson.
“We considered erecting a gantry from
which we could pick up the precasts and
lower them into place, however we would
have been snookered on the southern side,
due to the hotel and the through road.”
Interesting aspects of the
project
• A protection deck, consisting of a girder
system that spanned the 18-metre
wide main access road into the airport,
was designed and constructed prior to
work being allowed to commence over
vehicular traffic.
• The demolition activities had to be
undertaking in a way that reduced
environmental impact in terms of
excessive noise and dust pollution.
In particular noise levels, if not
controlled, can prove very disruptive, to
guest in the airport hotels and customers
using the Gautrain.
• To accommodate the increased loading of
the structure the struts were transversely
post-tensioned and the existing viaduct
was longitudinally tensioned.
• A new 68-ton steel roof canopy was
manufactured and installed.
• The construction method had to take into
consideration the mere 150 mm distance
between the southern side and the
adjacent multi-storey City Lodge carpark.
“The key to the success of this project
included a professional team and good plan-
ning that started from the conception phase
of the project,” concludes Deyzel. “Our site
motto was to ‘do it right the first time’, and
by setting ourselves realistic goals, we were
successful in achieving them.”
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