The Civil Engineering Contractor July 2018 | Page 23

Demolition vs refurbishment
“Demolition projects are generally
associated with forward-planning and
safety management. Clients would
typically opt to have a redundant
section of their plant demolished to
make way for expansion or growth,”
Bester says. “Alternatively, the cost
of demolition compared to the
maintenance and upkeep of a redundant
structure may result in the demolition
of the structure as part of the client’s
eventual plant-closure planning.
“We are also seeing an increase in
structures deteriorating beyond
the point of repair due to lack of
maintenance. We will almost always
encourage the demolition of those
types of structures before they reach
the point of becoming a risk to others.”
Almost a third of the buildings in
Johannesburg’s CBD deserve to be
condemned and demolished, if only
government had the budget, says
Richard Kelly, technical director at
Wreckers Dismantling. “Concrete only
has a certain lifespan, after which
it becomes a hazard,” he says. That
lifespan depends on the strength of the
concrete, but he explains, for example,
that many bridges and buildings in
South Africa date from the 1950s
and 1960s and consequently, cases of
concrete cancer are common.
He believes that refurbishment is not
an option in such cases. “At most, these
structures would only have a 10-year
lifespan left, even after expensive
renovation.”
Sometimes, infrastructure can
be demolished much sooner than
anyone could predict. Occasionally,
major infrastructure has a built-
in obsolescence: when South Korea
built a brand new Olympic stadium in
Pyeongchang to host the 2018 Winter
Games, the USD109-million 35 000-
seat stadium was only ever meant to
be used four times before it would be
demolished. That cost amounts to an
astonishing USD10-million an hour of
use.
It was built to be obsolete: the county
in which the stadium is situated has
only 40 000 people, and once all the
competitors and guests had left, the
stadium would be useless for locals. In
fact, this scenario is rather typical for
Olympic events, and even in the case
of South Africa’s hosting of the 2010
FIFA Soccer World Cup. Judging by
poor attendances at top-flight games
that do not involve the country’s two
most popular clubs, Kaizer Chiefs and
Orlando Pirates, it appears government
spending more than R9-billion on
stadiums alone was a resounding
waste of money. The absence of fans
at football matches has given affected
municipalities that own the stadiums
a huge headache, as maintenance costs
drain city coffers with little income
to offset that expenditure. Would
K
ate Bester, contract manager
at Jet Demolition, says, “The
industry has come a long
way since the days of ball-and-chain
demolition, and is now a profession
built on trust, experience, and proven
ability.”
The question of whether to repair
or demolish a structure is likely to
become ever more important as the
size of South Africa’s infrastructure
increases. According to a report
titled Infrastructure Insight: South Africa
by market research and information
service provider Ken Research,
the market value of South Africa’s
infrastructure increased by around
R70-billion during 2010–2015, a
trend which is set to continue as it is
anticipated to grow another R113-
billion by 2020. It predicted that
the market value of South Africa’s
infrastructure would have more
than doubled in just 10 years to
R335.3-billion.
The report looked at all key
infrastructure sectors, including
roads, railways, electricity and power,
water and sewerage, communication,
airports, and ports.
In the World Economic Forum’s Global
Competitiveness Report for 2015–2016,
South Africa (placed 59th out of 140
countries) ranks well ahead of other
major African economies in terms of its
overall infrastructure quality. Nearest
was Algeria at 101, Egypt at 114, and
the nearest sub-Saharan competitor
was Nigeria, ranked 133.
However, the risk with over-emphasis
on building new infrastructure at the cost
of not adequately maintaining existing
infrastructure is that the infrastructure
often requires demolition earlier than
might otherwise have been the case.
TECHNOLOGY
When the 68-year-old Mike Perkin began
his trade in 1966, it was with a jack
hammer and a 14-pound hammer.
Explosives weren’t used back then,
not even for 30-metre-high chimneys.
He learned his trade the hard way — by
exercising extreme safety and care as
structures were demolished virtually
by hand.
“Concrete only has a certain
lifespan, after which it
becomes a hazard. That
lifespan depends on the
strength of the concrete.
Many bridges and buildings
in South Africa date from
the 1950s and 1960s
and consequently, cases
of concrete cancer are
common.”
Richard Kelly, technical director at
Wreckers Dismantling
demolition be a cheaper long-term
option?
Kelly says that Wreckers has been
involved in a number of demolitions of
structures (often just the steel frame)
of buildings condemned before they
were ever complete: one structure
in Nigeria’s Abuja, and another in
Tshwane.
Types of demolition
• Implosion: This i