The first experimental road section of 350 meters currently shows very good results.
“The task was to improve properties for bitumen binding. It's an adhesive for fragments and particles of stone. This substance largely determines the longevity and properties of asphalt concrete at low and high temperatures,” said RTU lead researcher Viktors Haritonovs.
Tire rubber is already used elsewhere in the production of asphalt concrete, but powder is usually applied instead of granules.
“Solutions with the addition of crushed tire powder to road bitumen coverings – there are no big problems. The problem is to grind the tire to the powder, a lot of energy needs to be applied, and this is a very expensive process. In this case, larger pieces have been used [..],” – said Ivars Kalviņš, president of the Latvian Academy of Sciences.
The new asphalt was tried on a busy section of the road through which heavy machinery moves everyday.
“The road section is about 350 meters long, one lane three meters wide. Adjacent bands are the reference band where the modified bitumen was not used. This will make it possible to compare,” explained Haritonovs.
In the years to come, scientists have to regularly monitor how the new surface of asphalt concrete behaves. Initial studies have shown that this should be good and sustainable for both loads and temperature fluctuations. This study is likely to have both extensive practical uses and economic benefits in the future.