Rubber Journal Asia Materials News
Paving the way for rubberised roads Rubberised roads demonstrate a viable
Persuade’s PERS mixes were tested on tracks such as the 75-m road built in Kalvehave, Denmark in 2014
solution against greenhouse gas emissions,
road noise abatement and landfilling of scrap tyre rubber. In Thailand, rubber roads also
stabilise its economy, says Angelica Buan in this report.
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raffic on roads, the blight of economic growth, has health, environmental and productivity costs. INRIX, a US-headquartered mobility intelligence company that provides traffic analytics and population movement insights, indicated in its 2016 scorecard report that among developing countries surveyed, Thailand, which also ranks first worldwide, leads in peak hours spent in congestion, with an average of 61 hours. Meanwhile, Russia leads in the developed countries category and ranks fourth worldwide with an average of 42 hours spent – and wasted – in traffic jams. On the other hand, people in countries like Italy and Singapore spend fewer hours on roads, averaging 15 and 10 hours, respectively. The growing population and urbanisation are also major causes of road congestion, according to INRIX. It is a crisis that is also tied up with the state of infrastructure of a given region, country or city. In other words, road congestion is a malaise that has not found a perfect cure, as yet. However, there is something that can be done to cure its symptoms: among which is road noise.
this project might include also a certain amount of sand or stone aggregate, mainly to increase friction. PERS has been initiated in Belgium, Denmark, Poland, Slovenia and Sweden, where full-scale test tracks with different stone/rubber/binder mixes of varying length were built; and on roads carrying different traffic loads. Large amounts of recycled rubber from scrap tyres were used. The Persuade team also monitored the tracks for a variety of parameters, such as skid resistance, winter behaviour, noise reduction and durability. According to the team, it “achieved initial tyre/road noise reductions around 10 dB with the best PERS materials, exceeding that of average noise barriers. All the materials tested on roads exposed to traffic met road administration requirements concerning skid resistance. Performance during winter conditions was also acceptable overall. Procedures to handle early snowfall and ice formation events were developed, including preventive and extra salting”. Another important advantage of the materials used in PERS is that they do not create chemical hazards during construction or operation, Persuade reported.
Keeping the level of noise down on roads ow to dampen road noise is the main objective of a European project called Persuade. Launched from 2009 to 2015, the EUR3.4 million, 12-partner consortium focused on developing and testing new road pavements with very high noise-reducing effect. They recommended a formula for poroelastic road surfaces (PERS) that are based on recycled tyre rubber, and with a high proportion of air voids to make the surface porous. The air voids in combination with the elastic rubber granules to make the surface flexible, contribute to dampening noise from the tyre-road contact. PERS may be used on limited areas with very high noise exposure, and where it is not possible or desirable to use noise barriers. Persuade further explained that by using rubber granulate from used vehicle tyres bound with elastic resin, specifically for this project, a two-fold environmental aim may be achieved: reduce noise from road traffic and at the same time give a considerable amount of used tyres in Europe a second lifecycle. The final mixtures produced in
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US test driving improvements in rubber-asphalt mix he US piloted asphalt-rubber road technology in 1948 with a mile-long span along Exchange Street in Akron, Ohio. It was befitting since Akron was dubbed the “Rubber Capital of the World”, being a home base to the world’s top tyre brands like BF Goodrich, Bridgestone, Firestone, General Tire and Goodyear. That first test drive for elastic road mix contained between 5% to 7% rubber additive and the remaining bulk with asphalt. It was only in 1965 that crumb rubber was incorporated to asphalt mix, repurposing waste tyres. Since then, the state has adopted wider use of rubberised asphalt, building what it calls “quiet roads” with decibel level of road noise reduced to as much as 12%.
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