According to new atlas, roads always seem to need repair, but changing the formula can help them last longer Australian researchers have now shown another advantage of adding rubber from old tires to asphalt - additional sun protection can help double the service life of roads before cracking
Anyone who has ever touched a road on a hot day knows that these things produce heat. Although they are in the outside environment every day, nothing can protect them from the sun, resulting in cracks and holes familiar to every driver.
In a new study, researchers at the Royal Melbourne Institute of Technology (RMIT) in Australia have found an environmentally friendly way to strengthen roads against the sun's rays. The key is to add crumb rubber, a material ground from rubber products such as waste tires. It has shown promise to make concrete stronger and more heat-resistant, and researchers want to know whether it can protect asphalt from UV degradation.
To test the idea, the team added crumb rubber to the top of the asphalt in three different concentrations - 7.5%, 15% and 22.5%. Then, the samples were placed in a machine and exposed to high levels of ultraviolet light for a month and a half, which is an accelerated aging process, equivalent to the situation of local roads in a year. Finally, the researchers measured the changes in the chemical and mechanical properties of asphalt.
The team found that the samples with the highest rubber concentration showed half the UV damage of ordinary asphalt. However, adding too much may begin to weaken the road's resistance to mechanical damage.
"We found that the addition of 18% to 22% crumb rubber produced an ideal balance in improving rutting and fatigue traffic loads, while resisting UV aging," said Filippo Giustozzi, the study's lead author. "It's as effective as sunscreen on the road. It actually makes the life of the road twice that of ordinary asphalt. We know that ultraviolet light can be a factor in road degradation, but we don't know how much it is or how to protect it, because no one has really studied this problem."
Another advantage of this technology is that it gives new life to old tires. These wastes are a major accumulated environmental hazard, so useful methods are welcome to recycle them.
The study was published in the Journal of cleaner production( https://www.sciencedirect.com/science/article/abs/pii/S0959652622009969 ) 》Come on.