With the price of patching up potholes warned to reach tipping point this year, researchers have found using infrared heating to repair roads could save millions.
Road repair bills in England and Wales could reach £14bn in two years, dwarfing councils’ highway £4.4bn budgets, the Local Government Association says.
The government said councils will get £10m a year from a new pothole repair fund, but the Local Government Association warns this won’t pay for a big backlog.
Devised by researchers at Brunel University London, the technology could save authorities £3.5bn in 2019, by making repairs cheaper and longer-lasting.
“Potholes develop when surface water is pressurised by travelling vehicles, opening cracks within the asphalt,” said civil engineering researcher Juliana Byzyka. “Wet weather, combined with cycles of freezing and thawing, dramatically accelerates pothole development.”
Both temporary and supposedly longer-lasting repairs often fail, creating dangerous driving conditions that put road users at peril, damage vehicles and dent the public purse.
“Occasionally, road maintenance teams use commercially operated heaters to repair potholes, but many instead deliver hot material to the site for filling and compaction of the pothole,” said Juliana. “We found that this leads to a higher risk of pothole failure due to inadequate heating at the interface between the pavement and fill material. A lack of temperature control deep within the mass also causes failures.”
Backed by engineering firm, Epicuro, researchers developed a portable machine that uses infrared heating to heat pothole surface and deep underneath before repair. A 3D thermal model is used to model and control the repair process.
“The Controlled Pothole Repair System is designed to be easily transported to repair sites and operates within a single lane of the road, so extensive road closures are avoided,” she added.
Dr Mujib Rahman, Senior Lecturer in Civil Engineering, said: “We spend ever increasing amounts on temporary and permanent repairs, often with inadequate results. This shows that through better understanding of repair fill material heating, we can deliver repairs that last a lot longer than their current life expectancy of two to four years. This can create better-quality road surfaces which would make for fewer accidents and smaller maintenance budgets.”