bitumen amid a nationwide shortage which is affecting the construction of roads, encouraging cement firms to dream of a shift to concrete roads. For years, cement companies have tried to get road authorities to choose cement which would then be made into concrete.
Yet bitumen has been
found to be cheaper and quicker to work with. This is even if concrete
roads last longer.
The South African National Roads Agency’s
(Sanral’s) multibillion-rand road-upgrade and road-building plans were
hindered last year because of shortages of bitumen, which stemmed from
unplanned shutdowns at refineries.
Bitumen is a sticky, black and
viscous liquid or semi-solid form of petroleum. It is made from the
distillation of crude oil. It has been used for years in SA to cover
roads and fill potholes.
The shortages meant South Africa had to import bitumen from Singapore and Malaysia at a premium of about 20%.
But road building firms such as Raubex and Basil Read have secured
supply for this year in order to avoid losses from delayed projects.
the past few years, more and more companies have focused on building
bitumen concentrated roads and not concrete ones. Some of South Africa’s
highways have been made from concrete, but concrete’s relatively poor
handling of rain, and related car accidents, has added to the popularity
Last year, road upgrade projects were affected in the
Eastern Cape and Cape Town, which included the MyCiTi Integrated Rapid
Transit feeder bus-stop contracts. Cape Town imported 4,500 tons of bitumen from Malaysia in May last year, says Brett Herron, mayoral
committee member for transport, roads and storm water.
construction company Basil Read fell behind schedule with its contract
for the N12 highway-Tom Jones Road project in Gauteng. As part of the
Gauteng Freeway Improvement Project, Basil Read is upgrading the Tom
Jones and Rietfontein interchanges on the N12 in the East Rand. But a
lack of bitumen slowed the project and cost Basil Read millions of rand.
builders have found methods to keep their bitumen work going. Basil
Read is establishing a plant in the Western Cape to maintain specific grade bitumen. Bitumen will be supplied from a Western Cape refinery
being built with the help of a New Zealand company.
Basil Read’s MD, Dave Bennett, is confident that bitumen supply countrywide will remain under control this year."We have our plant to support us, but even without it, the oil refineries are back on track.
are getting enough bitumen for this year. The main thing we need though
is for there not to be sudden shutdowns. At this stage, we just expect
to see maintenance work on the refineries when construction companies
close late in 2013 for builders holidays," he says.
He says concrete will not be used instead of bitumen, regardless of any threats to supply.
roads can be very good but they are expensive to build. They may last
longer but they also do not take to extreme weather like heavy rains
like bitumen roads do," he says.
The stretch of the N1 highway
between Johannesburg and Pretoria was mostly concrete, but a layer of
bitumen was added to it recently, because of the number of road
accidents in wet weather, he says.
"You’ll find that some of our
highways are concrete. They have been built to last. However, we must
bear in mind that they have cost a lot to build and the authorities
would only spend so much money on main highways in the future. These
roads are likely to have bitumen layers because of the experience of
accidents on the concrete highway from Johannesburg to Pretoria," Mr
Listed road construction and rehabilitation group
Raubex recently bought Tosas, a maker of value-added bituminous products, from Sasol Oil for R120m.The acquisition provides
Raubex with bitumen processing and storage facilities in South Africa,
and extends its footprint to Botswana and Namibia.
assessment of the strategic fit of the downstream bitumen business,
Sasol Oil decided to dispose of its interest in Tosas," Sasol group said
on Monday. Tosas makes modified bitumen, which includes rubber or
synthetic latex. It is a durable and more elastic product with greater
Raubex CEO Rudolf Fourie says the
acquisition gave the group the ability to work with bitumen in-house and
provides 50% of its bitumen needs.
Brian Perrie, MD of the Cement
and Concrete Institute, still believes there is a case for concrete
roads. He says cement is safer to drive on irrespective of the weather
threats. "It reflects light better than bitumen does, making it easier
to drive at night. It offers built-in skid resistance and improved
traction, for safer driving. It can be grooved for improved run-off,
preventing aquaplaning in wet conditions."
It is also quieter than
bitumen when cars drive over it, and raw materials, including cement,
sand, stone and water are readily available in South Africa. "Concrete
roads are viable in South Africa. They are quicker to build and require
labour intensive methods which empowers local communities and creates
employment. Concrete plants, unlike oil refineries, can operate all year
round," Mr Perrie says.
Pieter Fourie, CEO of cement firm
Sephaku, says he believes concrete should be the primary road building
material in SA because bitumen requires too much maintenance.
Source - BDLive