Several stretches of road in Sweden are too slippery to be classified as safe. This is shown by a new survey carried out by the Norwegian Road and Transport Institute, VTI.
Researchers at the institute had noticed a number of departures in places where they should not have happened and decided to take a closer look at the accident-prone stretches of road. It was found that a majority of the examined road surfaces had too little friction to be classified as safe.
– The majority have at least something with lower friction than the limit value and a couple of the sections had too low friction over the entire measurement section, says Henrik Bjurström, researcher VTI.
No exact reason why the roads lack adequate friction has not been determined, but the researchers’ theory is that reduced use of studded tires is an important factor.
– In Sweden, we build roads with very hard stone so that they can handle the studded tires without too much wear. When we drive with studless tires, the rubber rubs against the stones and then they become smooth, and during the winter the studs roughen them up. It’s an interaction that worked very well, until now when we no longer seem to get this roughing up, says Henrik Bjurström.
In the player above: Henrik Bjurström explains why several roads are classified as unsafe.