Ongoing research and development and the introduction of new technologies are among the key benefits that National Asphalt passes on to municipalities in meeting their current and future infrastructure demands.

Effective infrastructure roll-out and operation is at the heart of service delivery, and the private sector has a critical role to play in helping municipalities fulfil this important mandate.

“There needs to be closer collaboration between local authorities and their supply chain partners. This can only be achieved by introducing procurement systems at municipal level that incentivise greater involvement by the private sector in the planning, financing, operation and maintenance of these assets. This includes the vast and important road networks that fall under the watch of South African municipalities,” says Sean Pretorius, managing director, National Asphalt – a leading local asphalt manufacturer.

Pretorius believes that South African road construction companies have amassed a wealth of knowledge and capability over the years that can be better harnessed by municipalities. Companies such as National Asphalt are able to fulfil a greater role in municipal road projects by becoming involved in the project right from the outset in the conceptualisation and design stages. Its skills and expertise are also able to help municipalities maximise the socio-economic mandates associated with the building and maintenance of road infrastructure.

However, this ideal is reliant on drastic changes to the way in which infrastructure is being procured at a municipal level, “from one that is mainly driven by price to a model that takes a longer-term view of these assets,” says Pretorius.

Technological expertise, R&D

In addition to the skills and capacities, it is the extensive road construction technology that resides within the Raubex Group of companies that promises to add significant value under this proposed method of delivering essential infrastructure.

Many of these technologies are the outcome of years of research and development (R&D) geared at improving the overall quality of the country’s road infrastructure, and have been adopted by leading local road agencies, as well as other prominent public sector client bodies.

A stellar example of the ongoing R&D undertaken by the company in terms of road construction materials are the continuous breakthroughs in the use of reclaimed asphalt (RA) and Enrobé â Module Elevé (EME), or high-modulus asphalt in South Africa.

EME, which was developed more than 30 years ago in France, is a bituminous material with a high stiffness modulus, providing increased resistance to rutting, good fatigue resistance and sound durability. In addition to enhancing the design life of the pavement, it allows for a reduction in asphalt layer, while achieving the same design life of conventional asphalt, or even exceeding the specification.

Pretorius says that he has seen a marked increase in the adoption of this technology in the country over the years, including at municipal level.

KZN projects

For example, it has been successfully deployed on the construction of bus routes on the Go Durban projects through Kwadabeka and Newlands in the Pinetown region outside Durban, KwaZulu-Natal. The company is supplying about 84 000 tonnes of the material to the projects that are being driven by the Roads Provision Department of the eThekwini Municipality and the KwaZulu-Natal Department of Transport.

National Asphalt’s EME technology is also being used to repair major concrete failures on sections of Edwin Swales Road, the main access route to the very important Durban harbour.

Following on the success of these projects, Transnet Capital Projects has also approved the use of EME 20 as a 180 mm base alternative at the harbour’s Pier 2 at Bayhead.

These are complemented by other earlier road upgrade programmes where EME was successfully deployed.

This included the successful completion of a project for the South African National Road Agency Limited (Sanral) using a class 2 EME mix with 20% RA (reclaimed asphalt) on a section of road between Paradise Valley and Candella Road outside Durban.  The main contractor for this important project was Roadmac Surfacing, a sister company of National Asphalt within the Raubex Group of companies.

The significant work undertaken by the company in the field of RA promises to add even more value to both greenfield and brownfield road builds at municipal level.

Green infrastructure

This ongoing innovation in the field is in line with the green infrastructure agendas of leading client bodies at national, provincial and local government levels.

Just as important is the larger role that this technology is able to play in harnessing the vast RA stockpiles owned by a number of the larger municipalities.

Over the years, National Asphalt has refined the development and use of mobile asphalt batching plants. These plants can be easily deployed to various locations to assist road owners to easily integrate these resources into their road construction and maintenance programmes.

A similar approach could be adopted to effectively exploit the vast blast-furnace slag resources in the country.

Over the years, these types of industrial by-products have become an important substitute to virgin materials in road construction. They have replaced virgin materials, especially aggregates that are used to build the foundation layers and used in the surface seals and asphalt overlays of the road.

As such, Pretorius tells IMIESA that the use of slag will continue to be a strategic thrust for National Asphalt over the next couple of years.

“I believe that there is still much that can be done with these industrial residues that continue to prove their quality traits in the international road arena. There is significant potential to increase the use of reclaimed-type materials in municipal and similar road networks,” he says.

Demand for better infrastructure will continue to grow considering the rapid rate of urbanisation in the country. Faced with a growing backlog in road maintenance, municipalities will come under more pressure to maintain existing, and develop better, infrastructure.

Pretorius says the solution lies in embracing cutting-edge road construction technologies that not only prolong the overall life cycle of these strategic assets, but also facilitate and optimise important maintenance regimes of municipalities.

This immense responsibility cannot be shouldered by the public sector alone. Perhaps the ongoing successes enjoyed on the strategic national road arteries that are being operated by concessionaires under the Sanral banner point to a future model for local road networks?

Meanwhile, the introduction of private sector players into the construction and operation of other essential infrastructure in the country, such as water, could also act as a blueprint for the better management of local road infrastructure.

One thing is for certain: there are companies with long and proud track-records in road construction in the country that are ready to assist government to deliver better road infrastructure. National Asphalt is definitely such a company!