Thabo Mohlala
Although more than 70% of road fatalities in South Africa are due to human errors such as drunk driving, speeding and pedestrian walking, poor road infrastructure is seldom mentioned as one of the major contributing factors.
Yet according to road and infrastructure experts the terrible state of most roads across the country is also to blame for the 30% or so of the roads accidents or deaths. They attribute this to lack of regular maintenance as well as the use inferior surfacing materials or products.
But the situation is set to improve according to the Council for Scientific and Industrial Research’s (CSIR) new research, which is aimed at “providing alternative product and knowledge routes for the asphalt pavement industry”.
The intention, said the CSIR, will not only contribute to better performing roads but also to create jobs by way of including more players. The research body has partnered with Much Asphalt -one of largest commercial supplier of a range of hot and cold asphaltproducts to the road construction economy – to ensure better quality and durable road surfaces of roads in South Africa. The collaboration has seen a successfully constructed stretch of a road in Roodepoort, Gauteng.
The critical component of the initiative is its focus on “locally available alternative additives that would be much cheaper than the conventionally imported additives”. It will also lead to the creation of sustainable use of recycled materials that will not only yield an “economic benefit for the industry”, but will also address the country’s environmental challenges.
“After just over a years’ worth of combined laboratory development and evaluation efforts between CSIR Smart Mobility and the Much Asphalt Gauteng Regional Laboratory, the project came to fruition when both products under development were produced and paved into a controlled trial section in Roodepoort, Gauteng,” according to CSIR.
Senior researcher and manager of CSIR’s Advanced Material Testing Laboratories, Georges Mturi, elaborated further: “During both the development and trial phase, several performance characteristics were evaluated as predictors of in-situ performance, which served as the baseline for the in-situ performance evaluation that were set to run on a three-monthly basis for at least the first year after construction”.
He added that their assessments and visual inspections showed that after nine months of being exposed to environmental and traffic pressures the layers are performing as expected. “To date, no edge breaking is present where heavy vehicles are moving onto and off of the surfacing, no permanent deformation is present on the surfacing, with particular focus at stopping locations or where vehicle turning takes place and, to date, there are no signs of any deflection or temperature-induced crack formation taking place,” Mturi said.
Much Asphalt Regional Laboratory Manager, Joanne Muller, said “The developed and trialled technologies, aimed at improving the performance properties of standard 10/20 based EME, as well as having a viable replacement product for standard styrene-butadiene-styrene (SBS) modified A-E2 binder without detracting from pavement performance, are deemed effective and that can assist industry practitioners in the endeavour to provide long-lasting pavements to society”.
It is believed that the technology developed through this collaboration will make it easier to correct poor bitumen products “to pass performance specifications”. Or that it will enhance the performance of standard bitumen from one grade to another when there is a national bitumen shortage, said the CSIR.
According to CSIR, the major benefit and highlight of this invention for the country would be an increase in the recycling of waste tyres in the road industry for the benefit of better-performing roads.
