Highways England is currently testing sunflower oil capsules as a means of preventing pothole formation by filling cracks in the road. A study carried out by a team of engineers at the University of Nottingham in the U.K. has revealed that the cooking oil does not make the road more slippery or any less durable as previously thought. Instead, the researchers have found that sunflower oil actually allows asphalt to "heal" itself. This reduces the need to close the road and fill the holes, the experts say.
"Our preliminary results showed that the capsules can resist the mixing and compaction processes without significantly reducing the physical and mechanical properties of asphalt and they also increased its durability. More importantly, we found that the cracked asphalt samples were restored to their full strength, two days after the sunflower oil was released," lead researcher Dr. Alvaro Garcia stated.
The Highways England trial is slated to cost more than 88 million British Pounds per year in order fill in the potholes in England’s roads. The scientists have stressed that using the cooking oil, which is priced at around 1.15 British Pounds per liter, is a relatively cheap solution to remedy the traffic hazard. The trial will work by making bitumen less thick so that the sunflower oil can easily seep into the cracks in the road. Bitumen is the sticky black substance that is used in road surfacing, the research team explains.
"We know road users want good quality road surfaces, with fewer potholes and not as many roadworks disrupting their journeys. This self-healing technology could give them that and offer real value for money. So far the Nottingham University research we have funded is showing real potential in how easy it is to mix and apply, as well as being sustainable and environmentally friendly," adds Robin Griffiths, senior pavements adviser for Highways England.
Potholes are formed when direct sunlight causes the roads to swell, while temperature drops in the evening cause them to contract. These variations in temperature, combined with the weight of the traffic, cause cracks to appear. These cracks are then exacerbated by rainwater that freezes and expands overtime. Potholes are known to cause massive damage to vehicles and are found to put the pedestrians' lives at risk. (Related: City infrastructure crumbling as NY subway trains now being held together with ZIP TIES.)
In fact, data from a Kwik Fit research have revealed that about four in 10 motorists in the U.K. have been forced to take evasive action in order to dodge a pothole. Likewise, the findings have shown that one in five drivers have had to swerve towards oncoming traffic to avoid hitting one. The results have also revealed that 7.6 million motorists suffered pothole damage to their vehicles despite their efforts to swerve and avoid the depressions. The researchers have found that these incidents have incurred more than 473 million British Pounds in repair bills.
The findings have also shown that aside from switching to the opposite lane, motorists tend to engage in other risky driving behaviors to avoid potholes such as excessive braking, hitting the curb, and mounting the sidewalk.
"Potholes originally took their name from being the size and shape of pots. But as consecutive freezing winters take their toll on Britain's roads, in many cases it would be more accurate to call them craters or chasms. The big worry, aside from the huge cost to motorists in the damage they cause, is that these craters can lead to drivers putting themselves and other road users at risk as they swerve to avoid them," Kwik Fit chief executive Ian Fraser has told The Daily Telegraph online.