ASPHALT AND BITUMEN MODIFICATION IN ROAD CONSTRUCTION
Road authorities across the globe know that using modified asphalt in new road projects is good business. It is cost-efficient in the medium and long term because the roads are less prone to rutting and cracking. This reduces maintenance, which is both a financial and a traffic-related problem as roads must be partly closed during maintenance work.
The most common way to modify bitumen in modern road construction is to use SBS (styrene-butadiene-styrene), a synthetic rubber. SBS is made from scarce virgin resources and is not only costly from an economical point of view – but also environmentally. However, SBS as a bitumen modifier can be substituted by coarse, recycled rubber powder (0.2-0.8 mm). This has now become a standard technology with years of practical experience across the globe.
Genan has launched Road+ as a third generation elastomeric asphalt and bitumen modifier. Road+ is used in compliance with a process patented by Evonik. The ingredient mixing ratio is 100 parts of high-quality Genan rubber powder with 4.5 parts of Vestenamer®, a semicrystalline polyoctenamer produced by Evonik.
A standard asphalt modified with 10% Road+ performs at the same level as or even better than a similar asphalt modified with 4% SBS. By using a product derived from scrap tires, you choose an eco- and climate-friendly solution.
FLEXIBILITY IN THE FIELD
Earlier generations of rubber asphalt were sticky, requiring special handling equipment. Road+ modified asphalt boasts extremely good adhesion to the aggregate but does not stick to the equipment. No special equipment is needed for the handling of Road+ modified asphalt in the field; nor do tanks and trucks need to be cleaned with release agents. Road+ modified asphalt can be applied at a wider temperature range than can traditional, modified asphalts. This is not only an advantage in the case of compaction but also in connection with manual operations, e.g. around driveways and on curves.
WHERE TO USE ROAD+
Road+ can be used in any asphalt and bitumen application, may it be stone mastic (SMA), all kinds of asphalt concrete (AC), porous asphalt (PA) or mastic asphalt (MA). Unlike SBS, Road+ may be used in any kind of bitumen, whichever origin. Road+ can be applied in SAMI (stress absorbing membrane interlayer) at high concentrations.
Prof. Dr.Ing. Damm, Hamburg, scientific consultant for asphalt concrete research, states: “Road+ modified asphalt improves the performance of all types of roads from smaller country roads over heavily trafficked motorways to industrial properties. The use of the Road+ system for all these different applications shows the full scale of its elevated technical properties.”