April 26, 2013

Bitumen Shortage- A relook at Cement Roads

South Africa is working to boost the supply of 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.

Over 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 of bitumen.

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.

Listed 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.

Road 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.
"We 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.
"Concrete 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 Bennett says.

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.

"Following an 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 temperature stability.
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
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