The Civil Engineering Contractor July 2019 | Page 17

ON SITE
Gauteng Piling's Nico Maas on site.
accommodation market leader
developers in the country. Lapalaka,
in conjunction with Khune-Con as
the main contractor, has developed
1 600 beds in Auckland Park, 1 700 in
Pretoria and another approximately
1 000 planned for Auckland Park.
Considering the strong demand
for student accommodation, there
are a number of developers which
specialise in buying plots of land
around all universities nationally
to develop into student digs.
There is considerable innovation
in this specialisation: one site in
Braamfontein has deployed attached
40-foot containers as rental units.
Scope of geotechnical
work
The piling contract was awarded to
Gauteng Piling — whose expertise
and fast establishment capabilities
satisfied the client’s requirements,
believes Gauteng Piling founder and
CEO Nico Maas. The contract is for
the installation of 128 piles, about
6m deep, at a value of R800 000. The
www.civilsonline.co.za
piling involves about 170m 3 concrete
and about 7t of steel in the piles.
Maas says the Cookham Road site is
“very straightforward for us”. The site
is level, but during rainy times it get
slippery, which makes it difficult to
move the machines and the concrete
trucks on site. Indeed, the site visit
took place during the height of
the April rains (which saw floods
in KwaZulu-Natal) and as some of
the photos indicate, extremely wet
conditions prevailed on site.
Quite apart from rain — which
project manager for Khune-Con
Wick Burger says was not unexpected
and had full contingency plans for —
Maas says: “The piles have water from
about 4m and special care has to be
taken to pour the concrete before the
water gets into the pile holes. When
it rains and the platform gets wet it is
impossible to move and the site was
closed for some days. There were no
specific complexities about the site,
but the safety file took some time to
get to the specialist’s satisfaction.
“What was important for us was to
get the soil report so we know what’s
beneath the surface. We’ve done a
lot of work in this area, and while
our current site is straightforward,
we did piling on a site just across the
road which was a nightmare because
the underlying soil was very wet and
collapsing, requiring special piling
methods. In the area around Wits,
there are lots of dykes and faults in
the geology – and you can get water
damming up against such a fault. If
the water is dammed up on one side,
there’s typically no water on the
other side,” says Maas.
The process consists of drilling
the piles, and once the required
depth is reached, the concrete is
poured immediately, at which point
a reinforcing cage is inserted. It is
thereafter filled to the exact top of
pile height. Pile done.
In this instance, the project
benefited from a quality geotechnical
report, says Maas, taking the
guesswork and risk out of the project.
He emphasises the importance of the
report: “I’ve had jobs where we make
a 50% profit, but also a job where
we’ve made a 200% loss.”
“I knew an Irishman who used to
say, if you drill down six metres, at
that level the soil has supported the
earth above it for millennia and it will
consequently support anything – and
most of the time he was correct. But,
in the Democratic Republic of the
Congo, for instance, you could push
a 13m rod down into the ground
by hand, and then you really need a
geotechnical investigation.”
On site, Gauteng Piling has a single
full time employee, the supervisor
Victor Mudau — all the rest being
hired via labour brokers, an efficiency
which means they only employ people
when there’s work. Maas claims this
is precisely why Gauteng Piling won
the contract, and many others like
it — “because we’re lean and mean”
with minimal head office overheads.
Maas has a word of advice for
new civil engineering graduates: “You
should be prepared to get out and
get your hands dirty. Too many of
today’s graduates want to sit behind a
computer all day — you don’t learn
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