MODIFICATION OF ASPHALT AND BITUMEN IN ROAD CONSTRUCTION
Throughout the world, both local and national authorities know that it is good business to use modified asphalt in new road projects. It is cost-efficient both medium- and long-term, because roads are less exposed to rutting and cracking. This reduces maintenance, which is not only a financial problem, but also 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 the synthetic rubber SBS (styrene-butadiene-styrene). SBS is made from scarce virgin resources and is thus not only costly from an economical point of view – but also environmentally. However, SBS as a bitumen modifier may be substituted by GENAN FINE rubber powder (0.2-0.8 mm); and this has now become standard technology with years of practical experience throughout the world.
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 mixing ratio of ingredients is 100 volumes of high-quality Genan rubber powder mixed with 4.5 volumes 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. And by using a product derived from end-of-life tyres, you choose an environment- 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 areas. The use of the Road+ system for all these different applications shows the full scale of its elevated technical properties.”