New technology to slash road repair bill
Researchers
at the University of South Australia have developed a protective coating
technology with industry partner RoadSave Holdings that extends the life of
deteriorating roads while saving governments and councils millions of
dollars in road repairs.
The RoadSave protector is an energy-saving, environmentally friendly water-based coating made by using a high volume of recycled crumbed rubber combined with a strong polymer adhesive employing a unique nanotechnology approach. The coating sticks firmly to a road surface and has superior weatherability, according to research scientist Dr Naba Dutta at UniSA’s Ian Wark Research Institute.
“Sourcing rubber from used tyres is an important aspect of this development because such rubber is flexible, elastic and wear resistant, and helps to solve an environmental waste management problem of used tyres that do not break down with time,” Dr Dutta said.
A normal road surface compound is degraded by sun, weather and other environmental factors over its life until it loses the ability to bind the road particles together, resulting in cracks that allow damaging moisture into the lower layers – creating potholes, deterioration and eventual structural failure.
Current resurfacing costs are high because damaged road surface layers are sometimes removed and replaced with new material. If degradation of a road is allowed to continue, the cost of repairing the road escalates due to the need to remove and reconstruct all of the road layers, creating major disruption for residents with noise, dust and inconvenience in their streets.
With the new technology, the damaged road surface is not removed. Cracks and potholes are repaired and the surface is then sealed with the coating, according to RoadSave Managing Director, John Pollard.
“The RoadSave formula literally ‘stops the clock’ on further degradation of road surfaces by protecting the asphaltic binder (adhesive) that holds the road surface together,” Pollard said.
“The liquid coating is simply applied by a small work crew using light equipment, with the surface dry and ready for vehicle use in only a few hours, unlike conventional resurfacing which can result in road closures and disruption for several days.
“This is a major asset management tool that substantially extends the life of existing roads, saving councils and taxpayers significant cash outlay. On average, RoadSave sealing is about one-third the cost of a conventional asphalt resurfacing and one-fifteenth the cost of a total reconstruct,” Pollard said.
The Australian Local Government Association this year said Australia's local road asset - worth $75 billion - is declining. Covering 680,000 km, local roads comprise nearly 85 per cent of the Australian road network. Councils commit around $2.7 billion a year to local road maintenance and renewal.
Most local government organisations aim to reseal roadways every 15 years, but research shows that roadways which have the coating applied from six years after construction will not degrade further if the spray is reapplied at about eight-year intervals.
UniSA and RoadSave are in the final development phase of the product, with site testing and client contact underway. The North Plympton company is also in advanced discussions with major service companies in Australia over the possibilities of a joint venture.
RoadSave has received an important Federal Government grant to move towards a commercial market release and is pursuing national and international patent protection.